Sex trouble, im only 19, why am i having trouble keeping an erection during intercourse

when im with my girlfriend and things lead to intercourse I physically cant have sex with her. for some reason I cannot keep a full erection, and it makes it impossible to get inside of her. during foreplay and such I have a full erection but when I put a condom on and attempt to have intercourse it just dose not work....im really embarrassed at that I cant please her. She thinks its her fault because she too tight, which may be it, but that dose not explain the loss of erection. I did some resaerch and some people say its a form of performance anxiety, but im not sure. I see all these commercials for ED drugs but im only 19! And im scared that it might be that!!. but im really not sure. Please tell me what I can do to fix this!

Interesting situation, but you'd be surprised that this is a problem faced by many guys. For example, I know someone who is like you - loses his erection when he tries to do it with a condom on - he even loses his erection when it gets wet - like with lube. Unlike you, he is circumcised.

I believe the problem may be in two parts:

1. You masturbate often - I'd say more often than you should

2. You are not so hot on this girl you are trying to have sex with.

Exercise some self-control and cut down on the number of times you masturbate in a day and more so in a week - try and reduce your masturbations to 2 or 3 times a week. This will help you build stamina and make you hornier (therefore have harder/stronger erections).