Hi, I'm 27 and had some performance anxiety erection problems last months, causing me to loose erection sometimes during intercourse. Anyway, last night I was expecting to have sex so took one 100mg Viagra pill around 9.30PM. Had sex about an hour later and all was good, strong erection throughout the intercourse, no matter I was nervous about it. After I ejaculated the erection normally went away. Girl went home so I went to sleep around midnight without erection. However, I woke up around 6AM with a strong erection and a mild headache, which I know is a side effect of sildenafil. I remember I had some erotic content dreams before waking up. I just wanted to sleep and didn't feel aroused at all but the boner was there. So I masturbated and the erection went away after ejaculation. However, it fully came back just few minutes later. I masturbated again and after second ejaculation the erection definitely went away, so I fall asleep. Woke up around noon, again with a strong erection. Masturbated again and it eventually went away after new ejaculation. I will accent that there was no any pain in my penis at all, only a mild headache. So I am a little worried as there is a possibility that my erection over night was lasting for hours while I was sleeping, could it make any damage to my further erectile function? Thanks in advance! John