Must I make up for the days of fasting in Ramadan during which I masturbated without performing ghusl, and swallowed my nails out of ignorance and negligence, keeping in mind that I was an adult at that time? And what should I do regarding the fasting of Ramadan in the past five years, where I fasted without praying due to obsessive-compulsive disorder? And should I prioritize making up for the days I did not pray, or the days I am required to make up for? And is my act of making the sign of the cross and calling out to Christ, especially since I despise Christians, considered disbelief from which there is no repentance for me? And am I suffering from jinn possession due to the scattered shivers that affect me when I hear the Quran or any religious speech, and my hatred for prayer, fasting, and ruqyah? And what should I do about all these matters?

The question implies you believe you have been afflicted by jinn ( demonic possession ), so I advise you to recite Ruqyah (Islamic exorcism) frequently. Masturbation invalidates the fast and requires making up for it. Neglecting to perform ghusl (ritual bath) for days during Ramadan is a grave sin, but the fast is valid if you did not do anything that invalidates it. Swallowing nails invalidates and breaks the fast according to the majority of scholars. Therefore, you must make up for the days in which any part of the nails reached your stomach. Neglecting prayer due to fatigue is not an excuse, as prayer is obligatory in all circumstances. You must turn away from obsessive thoughts about the Divine Essence and seek refuge in Allah from them. However, intentionally transgressing against or cursing the Divine Essence is an act of disbelief (kufr), but repentance is accepted. You must maintain your prayers and repent for past shortcomings in them. You should also hasten to make up for any missed fasts, along with repentance for intentionally breaking the fast. Continue your psychological treatment, do not pay attention to obsessive thoughts about faith, and hold firm to your faith. The door to repentance is always open.