Welcome to the forum.
HIV and most STDs are sexually transmitted only by insertive vaginal, anal, or (rarely) oral sex. Genital apposition -- e.g. your penis rubbing a partner's anus -- carries no known risk for HIV. There are theoretical but rare risks for transmission of skin-to-skin STDs like herpes, HPV, and syphilis. Condom-protected anal sex is risk free, assuming the condom remains intact. Fingering is no risk, and "protected" rimming (presumably with a latex dam, plastic wrap, etc) is risk free.
So the only part of your exposure that has any conceivable risk is your giving unprotected oral sex to your partner. The HIV transmission risk for the oral partner in such exposures, if the penile partner is infected, has been estimated at 1 transmission for every 10,000 events -- equivalent to giving BJs to infected partners once daily for 27 years before transmission might be likely. If there was no ejaculation in your mouth, it's probably even lower. There could be risks for oral gonorrhea or herpes.
So both this and your past exposure have not been "just lucky". Beyond the decision to have commercial sex at all, and to choose transsexual partners, you have participated in safe sex. While I cannot guarantee you don't have HIV or an STD, if I were in your situation, with my knowledge level, I would be comfortable continuing unprotected sex with my wife. However, people with sexual histories like yours ought to have routine HIV and STD testing (gonorrhea, chlamydia, syphilis) from time to time, like once a year. So although testing isn't necessary on account of this particular event, if this is something you do from time to time, you should consider testing if you haven't done so recently.
In the 1970s and 1980s, a few studies reported sore throat as being more common in STD clinic patients who had performed oral sex, either fellatio or cunnilingus, in the preceding week or so. No STD was found to be associated with the symptom; for example, the frequency of oral gonorrhea was the same in such persons with and without sore throat. One idea is exactly as you state, that deep oral penetration may cause mild trauma that is painful for a few days. Alternatively, sometimes maybe a garden variety cold virus is the culprit. Whatever the cause, pain usually goes away in a few days, no harm done.
I hope this helps. Best wishes-- HHH, MD
That was very informative and thank you. I must note that the rimming was unprotected. Does this change your evaluation at all? I screen about every 3 months and will begin early detectable infection screening in about a week. Hopefully this episode has spooked some sense into me because I'd rather spend my money on evaluating and overcoming my risky behavior, rather than indulging in it and putting myself and others at risk.
Rimming risks enteric (intestinal) infections, but is generally believed to be very low risk for HIV and other STDs.