I would seek the counsel of a learned and holy Priest, whom I suggest you choose as your spiritual director. Such a cleric alone would have the graces of state in order to accurately gauge your particular predicament. Layfolk ordinarily lack the competence and science wherewith to guide you properly. All they can do is offer their opinions, impressions, hypotheses, etc., in a spirit of fraternal charity.
The following does not necessarily apply to you, but are general remarks:
In my experience, those interior souls who have acquired sinful habits against the 6th and 9th Commandments and earnestly strive to conquer the same, but for some reason have not efficaciously and effectively overcome these habits, ordinarily are not called to the Sacred Priesthood.
The culpability concurrent with the acquisition of the above-mentioned sinful habits must be gauged according to the individual circumstances wherein the person contracted them: for example, someone who had been sexually abused as a child or had been exposed to indecent or pornographic material, or had been neuro-chemically predisposed to precocious sexual activity that substantially contributed to the psycho-sexual complexes that are very commonplace in the present day, may not be as culpable as those who willfully exposed themselves to proximate occasions of impurity as older adolescents and thereby lost their baptismal innocence. Nevertheless, even if there is little culpability to be imputed to the individual insofar as the manner in which the said habits were contracted is concerned, he as a person endowed with free will and a Christian that has access to the supernatural graces of prayer, the Sacraments, etc., will be culpable if he retards his progress in the interior life by cultivating these vices in the same way that other souls retard their progress in their own peculiar ways: to wit, the neglect of prayer, shrinking from exterior and interior mortification, refusing to offer to God the sacrifices He condescends to require of him (for He, being God, needs nothing from us, rather it is us who need Him for everything), neglecting docility to the Holy Ghost, etc. These defects will inevitably lead the soul back to the vices it heartily detests.
When it comes to purity, the battle is for most souls one that ends only with death. Such interior souls must neither give in that sort of complacency that can lead to spiritual blindness and abuse of grace (e.g. "Hey I prayed the Rosary this morning, so it doesn't matter if I see that Rated R film because I asked Mary to help me," or "Well, why not give in just for today. I can go to confession on Sunday"); or the apathy and discouragement that can lead to melancholy, acedia and eventually despair.
The battle is very difficult, so an interior soul that is assailed by these vices cannot contemplate the Priestly vocation, for such a sublime state presupposes a very great progress in the interior life (even reaching the threshold of the Unitive life) and a stable emotional and psychological constitution that is unperturbed by the violent temptations and vexations that are concomitant with the battle against impurity. As a Priest, one would have to bear the burden of all the souls over whom one will have chosen to exercise pastoral care, and that entails a very great spiritual, mental and physical strength that the souls above-mentioned necessarily lack because of their constant struggles.
It may happen that an interior soul such as the one in question does indeed have a Priestly vocation and at the present moment is fighting against violent vices of impurity. The sign that the vocation is of divine origin will be how generous, magnanimous, ruthlessly self-effacing is the soul in its zealous and earnest quest for greater prayer, self-abnegation, mortification and filial abandonment to God in offering Him the Crosses He deigns to send us (anything from stubbing your toe to a tragic loss in the family). Such an individual will indeed make progress in the Purgative life and overcome their vices to the point where they are ready for the passive purification of the senses that is a prelude to the Illuminative way of spiritual proficients. This will necessarily eradicate any residual effects that the vices may have left behind, even after being overcome. Such a man will be worthy of the clerical dignity, and his progress toward the Unitive life of the perfect should continue as he ascends through the Minor Ordes unto the Major Orders.
It also comes to pass that there are interior souls who have to struggle against vices but are exceedingly attracted to the Priesthood, whilst retarding their progress in the spiritual life by their neglect of the means of grace in their war against impurity. Even while they are degenerating, these souls still feel a strong proclivity to matriculate into a Seminary and attain to holy Tonsure and the other Orders. However, according to the cases I have observed, this attraction is not a vocation of divine origin, but rather a very perilous temptation whereby the devil seeks to entrap these souls and use them in order to profane Holy Orders and work the destruction of numberless faithful whom they will mislead or outright pervert with their tepidity and weakness. If the attraction to Holy Orders remains even after a considerate amount of culpable retardation in the spiritual life (especially if it proportionally increases as the soul fails to combat temptations), then it is definitely a perilous and veiled temptation, stemming from spiritual pride and complacency and artfully manipulated by the devil.
The scandals in the present day clergy may have their ultimate origin from such an above-mentioned delusion whereby unfit candidates for Holy Orders have seduced themselves into boldly and audaciously seeking and obtaining these Orders, to the greater destruction of their souls and those of the faithful over whom they pretend to exercise pastoral care. It is my private opinion that such a thing may be a sign of reprobation, if due penance is not done.
Again, these are general remarks, based on the cases which I have encountered. They may not apply to you, but they are made because I know for certain that you are not the only young man in such a predicament. People have no idea how many interior souls there are who face a similar situation and even worse...
I hope these notes may help you and others somehow, but please do seek the counsel of a learned and holy Priest. He alone can help you.
Be assured of my prayers