No need to go to a doctor, honey. Unfortunately for you guys, once you've cum that's pretty much it for a while at least. I've certainly never had a guy who's been able to stay hard enough to continue intercourse after he's cum. The penis is designed by mother nature to get hard enough to penetrate, and ejaculate as deeply into your partner as possible. After this happens, the penis' work is done (even if you or your partner wishes it wasn't!) and it no longer needs to stay hard.

Yeah, some guys stay hard for a little while after, but it's definitely the norm to lose your hard-on after you've cum - otherwise you'd be in a constant state of sexual arousal, and that could get pretty uncomfortable, not to mention embarassing!

Don't fret about it sweetie and if you're worrying about cumming before your partner and not being able to continue intercourse for her benefit, remember there are plenty of other ways to make a woman cum, and i'm sure she'll love you for trying them!!!!

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'Don't knock masturbation - it's sex with someone you love'

- Woody Allen