Venial sin is entirely up to you if you confess it in Confession.
That being said;  you are absolved of your venial sins every time you go to Mass.  The priest gives absolution just before communion IN THE TRADITIONAL LATIN MASS.  Otherwise people would have to go to confession before every communion.
However, it is good to confess venial sins 1) to help us overcome them 2) to receive the graces from confession.

I asked my Father after Mass today and he said no, but that it is a very very good idea to confess all sins. 

In my circuмstance I cannot be certain wether a sin is venial or not, and besides, as I posted originally, I will confess them all...venial or otherwise. 

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This is an important question. It's often overlooked because it can take a long time to answer it, and in such cases as catechism class or instruction on the Sacraments, there is a lot of material to cover, so going into detail on this kind of topic can consume too much time so that not enough is left for other subjects. We don't have that problem here on CI! Here, there's always plenty of time for everything!
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In its own small way this is like a little peek of paradise.
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It's a good idea to be considerate when you're in the confessional, as there might be other penitents waiting in line outside who have very few opportunities to confess, so you shouldn't take up time selfishly causing them to run out of time.
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But presuming there is sufficient time available, confessing venial sins is a good idea. Of course, you ought to focus on mortal sin first, so you don't forget about it, and it's a really bad idea to start with venial sins with the plan on working your way up to mortal sins. That's putting the cart before the horse, so to speak, and it's confusing to the confessor. 
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There was a saint (as I recall, St. Therese of Lisieux) whose confessor divulged after her death that it was his opinion that she had never committed a single mortal sin her whole life. Yet she had gone to confession every week for many years. Obviously, confessing ONLY venial sins is not an obstacle to sanctity! So how could it be bad?
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I knew one confessor, whose name I won't repeat, for he has passed away about 20 years ago, who was well-known to scold penitents for wasting his time confessing faults or small matters that he said were "not sins" for one reason or another. It seems he had made something of a career explaining away sin. He was a Jesuit in a local Novus Ordo parish (Northridge, CA). My mother, a pious lifelong Catholic, came back from trying to go to confession to him, crying that he had scolded her saying, "That's not a sin!" She didn't tell me what the thing itself was, but her emotional reaction was very meaningful to me. I had to wonder if such a priest was aware of the sorrow he caused by doing that. It was hard for me to imagine a priest behaving that way, so I looked into the matter in subsequent weeks. That's another story. Overall, it seems to me that it is a rare priest that would do that, and if you find one, he would be a good one to avoid in the future.
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A TLM priest told me one time that the Sacrament of Penance is one thing that Novus Ordo priests are doing okay with, that it's a sacrament that they are still doing properly. But I don't think that's correct. I have experienced a number of very strange things in Novus Ordo confessionals a description of which could go on and on and on. Suffice it to say that by FAR my best experiences have been confessing to TLM priests, without question.
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Recently I heard a sermon that piqued my interest, when the priest said that "Ego te obsolvo" are the most important words for the priest to say, because it means he is taking personal responsibility for the forgiveness of your sins. However, he said, in the new form for Newchurch "reconciliation," they allow the priest to say, "May God forgive you your sins..." thereby REMOVING from himself any personal responsibility, since he's literally saying he would hope that your sins are forgiven, but he wouldn't necessarily want any part of being sure they are. If that is really the case, then it follows that this is something that Novus Ordo priests are NOT doing properly.
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I have heard of priests who had the ability to read souls, but I have never encountered one personally. The Cure d'Ars (St. John Vianney, Patron of Parish priests) was one such priest. He came to Ars in France on assignment, and found a small town with rampant immorality and drunkenness, with far too many pubs for the population and customers stayed late into the night drinking at them. Fr. Vianney spent long hours in the Church, and did tremendous penances (eating burnt toast and drinking little water, taking "bread and water" to another, higher level). At one time they say he would spend 17 hours a day hearing confessions. People eventually came from far and wide to confess their sins. By the time he was finished with Ars, it was entirely converted and all the pubs had closed from lack of business. Peace was restored to families, the Church was busier than the pubs had been before, and the city was crime free. The devil was heard to say in an exorcism that if there were just 4 priests in the world like Fr. John Vianney, the devil's reign on earth would be destroyed. 
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Another priest who had the gift of reading souls was Padre Pio. I had the privilege of knowing some of his acquaintances, but I never met him myself. It's interesting to see how the character of a saint has the ability to "rub off" on his friends. Without knowing Padre Pio in person, I had the strong impression that I was meeting him through the intercession of those who did know him firsthand. Therefore, carried to the extreme, we can know what it would have been like to know the Apostles or even Our Lord Jesus Christ, by getting to know good priests who have spent their lives praying and working for Our Lord in the vineyard. Padre Pio would hear confessions, and not infrequently at the end of their description of their sins, he would be silent. The penitent might say something, like, "I don't have any more to say," when Padre Pio would reply, "Are your sure?" At that point, penitents had learned that they were in for a surprise. Because if they were unable to remember a mortal sin they had committed long ago, Padre Pio would describe it for them. He would tell them in such a way that it would take them back to the time and place in their mind and they could see it happening all over again even with their eyes closed. He was known to refuse absolution to women who had come to confess wearing dresses that were too short. Rememer, he could not see them in his confined quarters. He couldn't see their dress but he knew they knew what it looked like because he could see into their souls where their dress length was to be seen. They would have to go home and change clothes, then return to wait in line again, only to find that Padre Pio knew that this was their return visit even though they had not mentioned it. In this way we become convinced that if a mere man can do these things, imagine what God can do. 

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A trad priest told us that we should only confess venial sins if we resolve to not commit them again.  In other words, if you were to list the Top 5 or 10 sins you frequently confess, if some of them are mortal, then you should concentrate your spiritual progress on conquering the mortal sins first (obviously).  Then, maybe you pick one venial sin to also concentrate on improving.

If you get to the point where you are not committing mortal sins frequently and you are left with venial sins, then you would order those from the highest habit to the lowest habit.  Or, the hardest to stop vs the easiest to stop.  Then, you could start with the easiest venial sins to conquer and work your way up to the most difficult.

From a confession standpoint, if your personality is such that you are constantly impatient and lose your temper, this is probably a life-long struggle.  You know you need patience and you are constantly struggling, so confession should help.  However, if you notice that you have been wasting time on the computer or not being diligent in your daily duties (and this is not a normal sin for you), then you should confess this and resolve to amend this area of your life immediately.  If you confess wasting time and you aren't resolved to amend this area then that could, in a sense, be an unfruitful confession and you could lose graces for confessing something that you aren't ready to stop.

In other words, if you're trying to fight the battle of mortal sins because you're a partial alcoholic, then confessing that you have wasted time is not a bad thing, but it's not as important to your spiritual life.  You should be worrying about the more important sins.  Or, if you don't have any mortal sins to confess, but you come up with a "laundry list" of venial sins to confess but you have no plan how to stop these venial sins, then it's pointless, in a sense.  You should only confess venial sins that you are ACTIVELY trying to stop; confessing venial sins just to confess them can be counter-productive.  Focus on the main ones, defeat them, and then go to the next one.

That's the gist of what I got from the priest.  Take it with a grain of salt.

Listing all venial sins can become an exercise of scrupulosity.

I typically find one or two types of venial sins that I want to particularly focus on.  Going on for 30 minutes about venial sins hurts other souls who might truly require absolution from grave sin and may not get in during the scheduled time.  So, out of charity, I always limit these in Confession.

Some caveats here.

#1) Perfect Contrition only restores to a state of justification from mortal sin when combined with the intention to receive the Sacrament of Confession (per the Council of Trent).

#2) Perfect Contrition and the intention to confess do not completely "take the place" of the Sacrament of Confession.  This is the same imprecise language people use with regard to Baptism of Desire.  Even in such a scenario, it's the Sacrament that is the instrumental cause of the justification.  And people are still obliged to receive the actual Sacrament before returning to Holy Communion.

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How could someone be standing in line to go to Confession without having the intention to receive the sacrament of Penance? 
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What expectation could anyone have "to receive the Sacrament of Confession (per the Council of Trent)" while facing imminent death?

The Novus Disordo drops this? (It's been awhile since I've been to one.)
In the TLM, there are 9 prayers that forgive venial sins.

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In all Catholic rites there is an absolution from the altar by the priest, including the Eastern Catholic Divine Liturgies.
This is one of the things that characterize what makes a Mass Catholic.
In fact, it is even part of the Eastern Orthodox liturgy as well (even though Orthodox isn't Catholic).
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But it was abandoned in the unCatholic Newmass of Paul VI.
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Novus Ordo priests saying the Newmass never do the "second Confiteor" nor do they give absolution from the altar. 
(Actually they don't even do the first Confiteor.)