Our Lord will also come like lightning, which appears in the East and West simultaneously.

In short, you're not going to miss His coming!

He said in luke when he returns he will light up the sky's 

Really worried he's here and my last confession wasnt valid.

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Assuming the poster saying these things isn't just a troll:
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1. As Matthew said, when Our Lord comes at the end of the world, you'll know it.  There will be no question.
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2. Souls that love Our Lord should rejoice when He comes, not be "worried".  
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3. If you find yourself "worried" about Our Lord's coming, as another poster said, "Be ready. Always be ready."
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4. If you're worried your last confession wasn't valid, go do it again.  You should probably brush up on the requirements for a valid Confession.  Was there a specific requirement you purposely didn't meet?  e.g. You purposely omitted to tell a mortal sin?  If not, it was probably valid, and you're just having scruples.  Talk to a priest about this in your next Confession. 
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5. When Our Lord comes, whether in His Second Coming, or your own personal case - i.e. imminent death, make a perfect Act of Contrition to the best of your ability. 

But christ comes after the 7 year tribulation and after a blood moon with eclipse (which happend in January) he also said he willl brighten up the skies with his arrival and the skys are bright,,, I only think my last confesssion wasn't valid because I THINK HE IS HERE IN THE CLOUDES


It also said in the book of daniel ... the sacrifice will come to an end, blessed are those who wait three and a half years
i've commited a mortal sin this year, im in terror to be honest.

Terror of what? If Our Lord was here, you would know it without question, as would everyone else on earth, along with all the dead since Creation. When He comes again, it will be like you pray in the Apostles Creed; "He will come again IN GLORY to judge the living and the dead". When He comes again, the undivided attention of every created soul will be laser focused on Him all at the same time as the final judgment happens.  

No one, not even Our Blessed Mother knows when He will come again, the only thing we are certain of is that when He does come again, we had best be ready. So do not concern yourself with prophesies which are impossible to interpret correctly, replace that concern with growing holy as you grow old and keeping your soul clean.

but it said that the moon will turn blood red the day the Lord retruns, it marks a secret return?

Where does it say that?

It says when the moon turns blood red and the sun a sackcloth... well there was a red moon and eclipse in January

Is it possible hes here in the cloudes for three and a half years?

He does say, blessed are those who wait three and a half years and he will sustain you so you are blameless on judgement day?!?!

OP, you’re listening to Protestants!  Stop!   You don’t go to Heaven or not based upon getting your end-time theology right!  You’re confused and afraid.  Who is the author of confusion and fear?  Not the Holy Ghost!  Read, listen, watch ONLY CATHOLIC material for one month.  Watch your spiritual (and mental, emotional, physical) health improve.

That's why I don't believe in Garabandal.

He said when he comes he will light up the sky, the sky is looking brighter than normal