I cannot predict the chance either of your partners had HIV. But if there was unprotected anal sex (apparently you don't know), there could have been a chance of HIV transmission. If there was no anal sex, there was no transmission risk. (If you don't remember it, most likely it never happened.)
If you are quite certain unprotected anal or vaginal sex occurred, then you should immediately find a clinic or doctor familiar with HIV. I understand Hong Kong has excellent STD clinics; or you might go to a hospital emergency room. You need the immediate advice of someone who knows the epidemiology of HIV in Hong Kong and the local guidelines for post-exposure prophylaxis (PEP) with anti-HIV drugs, because you might qualify for it. For PEP to be effective, treatment must start within 72 hours of exposure, so don't delay.
In the meantime, don't panic. Even if one of your partners had HIV, and even with anal sex, and even without PEP, the odds against infection are in your favor. (With unprotected anal sex, the chance of HIV transmission is around 1 in 100.) Still, don't take chances; see an expert right away.
And if, as you think about it, you are pretty certain there was no anal sex, then just forget the whole thing. Without vaginal or anal sex, there is little if any HIV risk.
Good luck-- HHH, MD
if I take a PEP now, is that save?
I don't know exactly what you mean. Is PEP safe? Yes, although there are possible side effects.
Will PEP save you from catching HIV? PEP reduces the chance of infection, but is not 100% effective.
I saw a Doctor and he put me PEP madicine called Combivir.
how will this impact my job and normal life with the side effects?
Those are questions for the doctor who is treating you. That will be all for this thread.
Sorry to bother you, I'm now in Manila and can't follow up with the same Doctor, i tried to lookup for a Doctor who is familiar with STD here but no luck so far.
Just have two questions if PEP will impact normal life and work and also how will it impact my future health?
Most people have no side effects and there should be no effect on your future health.