Is a person considered a hypocrite if they are committed to acts of worship and obedience but fall into forbidden desires and then repent from them, or is that a trial from God? And are good deeds nullified because of these sins?

You are among those who have mixed a righteous deed with another evil one. You must abandon sins, strive against your lower self, and distance yourself from their causes. Your persistence in them may strip you of acts of obedience and lead to your heart being sealed and a bad end. We advise you to read the book "Al-Daa' wal-Dawaa'" (The Disease and the Cure) by Ibn al-Qayyim, for it elaborates on the effects of sins, and the door to repentance is open. Strive against yourself, and Allah will guide you to His ways. You are not a hypocrite, but there is fear for one who persists in sins of a bad outcome. This is a test from Allah, so overcome your lower self and amass acts of obedience and good deeds that expiate sins.