OK first off I'm 20... and for some reason I'm alrdy having problems with losing my erection during intercourse. I've been sexually active many many times with my previous ex girlfriend, no problems, always in the mood. I had a feeling she was cheating on me and we had a huge argument about it. That night we were going to have make up sex and it was the first time I just went limp? How does this happen? This is all I think about now and its affecting my new relationship. I met this girl, dating for a month now and the first time last week we had sex. Within 3 minutes we moved so she could be on top and bam I lost it. Completely limp. We talked the next day about it and she thought it was her but I told her it was me and I just wasn't in the mood that night. She later said it was seriously no big deal because she had an organism she just wished to have seen me have one as well. Now she is telling me everynite how she wants to have sex and I make excuses. Like I can't deal with this anymore... what is wrong with me? I really like her and want to pleasure her but I cant. She says don't worry about it but this is the most hurtful pain ever. Please can someone give some advice?

One idea is it could be a mental problem. You thought your ex girlfriend cheated on you, therefore you were physically unable to have sex with her. Maybe the thought of her cheating on you affected you more than you thought. Medically, it could be a case of erectile dysfunction, or ED. Some causes of this are:

Vascular disease
Diabetes
Drugs
Hormone disorders
Neurologic conditions
Pelvic trauma, surgery, radiation therapy
Peyronie's disease
Venous leak
Psychological conditions

My best advice would be to see a doctor to see if ED is the problem. If your doctor rules out ED you might want to consider counseling to deal with the psychological aspect of the problem.

Edit - ED affects all ages.

Your worry is the issue. It won't go up and remain erect while you worry-I KNOW!

You may have to ask her to not push it for the moment and enjoy each other's presence then move onto intimacy later.

Mental block.

Nothing like a little negative vibe to keep you off track.

You need a couple of "wins"... so, can you get her off orally? If so, do right by the girl, then its your turn. Don't wait for anything, don't try to do the right thing for her, focus on yourself.

Even if you aren't interested in the oral side, why not next time just focus on you, the sensations you are feeling. Yes, you want to be a gracious and giving lover, and that means pleasing your partner... that also means pleasing them by letting them please you.

So at least once don't hold back, wait, or make it all about getting her there. Its not rude to give a little, so its not rude to take now and then too.

And don't be afraid to tell the girl about the prior experience. You have a reason for that mental block... not your fault, not hers. But it might help her to understand there was a bad experience and you need to work that out of your system. It's the truth, like it or not.

May not be the problem but just how frequently are you having sex or masturbating? If its not every day or several times a day (in which case you're overdoing it) then maybe its just a stress related issue. Are you by any chance suffering sleep deprivation?

I hear stress is a BIG factor.