I'm 15 years old. I've never had ANY problem getting hard ever since I hit puberty. One day recently I decided I'd hold off awhile on masturbating, because I thought my girlfriend was coming to town in a week (didn't know where that might lead). Well, the week came and went, and a few days later I masturbated... I had trouble staying hard the whole time, even while watching porn. I had only a lazy erection when I ejaculated... Yesterday the same thing happened, except that the full erection lasted an even shorter time. Now I cannot get hard at all, no matter what. I've tried everything: stories, porn, thinking of my girl... nothing works. Help?