She "jumped on my erect penis" and you just couldn't help that it slipped inside her? And you couldn't get it out for 20 seconds? Hmm... why am I skeptical? I don't mean to be critical -- I just don't accept that the event was so involuntary on your part!
OK, so you had brief unprotected sex with a partner who may or may not be at high risk for HIV and other STDs. Clearly she intends to use condoms routinely, which is a sign she isn't infected and wants to stay that way. On the other hand, she obviously doesn't follow the condom rule consistently. All things considered, the possibility she was infected certainly is there. On the other hand, even among CSWs (in Singapore or elsewhere), the large majority don't have HIV. And if it is true that CSWs are "rigorously tested" in Singapore, that also is reassuring.
But most important, the risk of exposure doesn't matter. Test results always outweigh risk assessment in determining the chance someone has HIV or other STD. For reassurance and common sense, you should have blood tests for HIV and syphilis and a urine test for chlamydia and gonorrhea. Since you have had no symptoms and the overal situation suggests low risk, you can expect negative results. In this situation I do not recommend testing for anything else, like herpes, hepatitis, etc.
I hope this helps. Best wishes--- HHH, MD
Point taken doctor. I know I shouldn't have even put myself in that position in the first place, and I had ample opportunity to stop even the initial penetration.
At any rate, I'll get tested in the coming weeks and will stop unprotected exposure with my girlfriend during that time. Thanks again for the advice.