I am a 19 year old guy who thinks he might have a problem. I have had multiple willing partners to engage in sex with, except my penis doesn't seem to cooperate with me. It can be very difficult to get an erection, and sometimes keep one and i don't understand why and to be honest its driving me crazy. I usually masterbate once a day, supposedly thats what most guys do and i just want to know what i can do to get an erection whenever i want like everyone else seems to be able to, and to keep one. any tips or hints with be more then helpful. I feel as though i am 19 and at the supposed peak of my sexual life, i really shouldn't need pills or anything. But i'm open for suggestions.