I'm 23 years old and I urinate when I orgasm. I attempted to loose my virginity at 21 but I stopped because it was painful and it seemed like my boyfriend couldn't actually get in. Although before we stopped, I started to feel some pleasure but I did not urinate. I also do not urinate when I'm receiving oral sex. But I have been masturbating (clitoris stimulation) since my teenage years and when I orgasm I almost always urinate. It is less if I urinate beforehand but it is still substantial but I'm nervous that this will happen during intimacy also I do not want it to happen anymore period. My gynecologist, urologist, and general physician are lost for words. I was once prescribed Detrol but it was inaffective.
You should also start to do kegal exercises. Kegals will exercise and strengthen the PC muscles. These are some of the muscles that you use to stop urination. There are various exercise kits available to help you with it. These can be prescribed by your doctor. Perhaps you should have another talk to your doctor.
I am also 23 and have the same problem. It started while I was on SSRIs for anxiety/depression and it never resolved after stopping. I am in a relationship but my partner is left feeling inadequate since I never reach orgasm with him. I have tried faking it, which was probably the best way to deal with it. Once I told about my problem (I lied and said I am simply unable to achieve orgasm) things got worse. He doesn't initiate intimacy very often now. I feel so guilty, on top of everything else. If someone can figure this out please help me! Also I feel I should add that it is DEFINITELY NOT female ejaculation. I know what urine looks/smells like and this is urine.