Chances of exposure to Herpes

I was with a prostitute about 2 weeks ago.  There was mutual oral sex without a condom (fellatio and cunninglingus).  There was a short time of vaginal intercourse with a condom (about 1 minute) but the condom came off.  As soon as it did I felt it and pulled out.  I noticed a white discharge about a week later and was tested positive for NGU.  I just finished my anti-biotic regimen today.  However, I noticed a pimple-like sore on my left buttock that developed very quickly (about 1 day).  I popped it like a pimple and there was a little puss / fluid (couldn't tell) and now it has receded (although still very red).  I was nervouse about this being a sign of Herpes so I went back to the clinic today to be tested for Herpes.  The specialist drew blood and took a culture from the sore but said in her many years of experience she could say this sore was NOT Genital Herpes but some other type of staff infection on the skin that will go away on its own.  

Here's my question:  Although the NGU antibiotic regimen was completed today I'm still having testicular soreness and slight throbbing pain.  I read that groin area lymph node pain is a symptom of Herpes.  Could it be my groin area lymph nodes that are hurting and not my testicles?  I'm not sure.  Can there be testicular pain with NGU beyond the antibiotic regimen? How much stock can I put in the clinic specialist's certainty that the sore is benign (she also said we'll only know for sure if I have Herpes with the HSV Blood test, which I have to wait 2 grueling weeks to find out)?  Finally, based on the dual oral sex with the prostitute and the condom briefly slipping off what are the chances I contracted HIV?

Thank you very much for your time on this.

[H. Hunter Handsfield, M.D.]

Initial herpes generally occurs on the genitals, not the buttocks--even though buttock or thigh lesions sometimes occur as recurrent herpes.  However, the pimple you describe doesn't sound like herpes.  (Think of herpes lesions being superficial, i.e. "on" the skin, whereas pimples are deeper, "in" the skin.)

NGU rarely is due to herpes.  When it is, usually there also are classical herpes lesions on the penis at the same time.  Also, the NGU with herpes tends to be severe, with lots of pain, especially with urination.  Testicular and groin pain are not signs of STD, unless there is overt swelling and marked tenderness to the touch.  And groin or testicular pain alone is not a sign of herpes.

I don't know how much your clinic or the specialist you saw knows about STD.  If you were in a public STD clinic (or GUM clinic in the UK), you can rely on that person's expertise.  The things she told you sound pretty accurate to me, as best I can judge from your descritpion.  Most likely you can rely on her advice about your diagnosis and further testing--but it seems very unlikely to me that you caught herpes during the exposure you describe.

See many other threads about the virtually zero risk you caught HIV.  Search the STD forum threads for "HIV transmission risk" and "HIV anxiety"; you will find 50 or more questions on this, most of them more or less like yours.

Good luck--  HHH, MD