Welcome to the HIV forum.
The most important thing here is that you used a condom for anal sex. Good choice, and for practical purposes it means there is no risk of HIV from this event and low risk, but not zero, for other STD. There are slight risks, however, for you to have acquired oral gonorrhea, herpes, and other STDs; and smaller but still some risk for penile infection with gonorrhea, nongonococcal urethritis (NGU), or herpes from your partner's mouth. But I would not put any of these in the "serious" category.
At this point, I would advise waiting 1-2 weeks. If in that time you do not develop any symptoms -- pus or mucus dripping from the penis, sores of the penis, sore throat, sores/blisters on or around the mouth -- you can be fairly sure you didn't catch anything. For 100% assurance, however, you'll have to visit a health care provider for examination and testing. Your local health department STD clinic would be an excellent choice.
The main thing that concerns me here is that you say you asked your partner about his infection status after the exposure, not before. Men having sex with men must never have sex without discussing each other's HIV status before sex, not after; and you should then avoid sex entirely, or be super-safe (e.g., no anal, even with condom) for partners who are HIV positive, don't know, or seem evasive in answering. In the long run, this is just as important to avoid HIV as are condoms for anal sex. I call it "do ask, do tell". Follow this rule, and you can expect a long and rewarding sex life with little or no risk of HIV. Fail to do it and it's a good bet HIV is in your future.
I hope this helps. Best wishes-- HHH, MD
It is hard to imagine how having oral herpes would affect your professional life, and oral herpes generally has no effect on peoples' sex lives. But in any case, the risk for it is exceedingly low. (As an adult in the US or other industrialized country, there's a 50:50 chance you already have oral herpes anyway. Half of all adults have it, mostly without knowing it.)
Thank you doctor...
One follow up question... of all of those diseases is oral herpes a huge concern? I am worried that that is the one disease you mentioned that could affect my professional as well as sex life.
I realize HIV is deadly and will probably never engage in anything like this again.
Thanks