You're fine:  you definitely do not have HIV. In theory, it can take up to 45 days for a positive HIV AgAb (4th generation) blood test to become positive, but at least 98% of newly infected people have positive results by 27 days and 99% by 34-40 days. Equally important, if your symptoms were caused by a new HIV infection, your tests would all have been positive:  it is not possible to have HIV symptoms with negative test results. (Symptoms are not caused by the virus, but by the body's immune response. Therefore antibody always is present by the time symptoms begin.) I'll also point out that a single episode of unprotected vaginal sex with a female partner is a very low risk exposure, even if the woman has HIV -- and statistically it is unlikely your partner is infected. In addition, 27 days is much too late for onset for HIV:  symptoms of new infection, if they occur at all, begin 1-2 weeks after catching the virus.

So you needn't be worried at all about HIV. If you feel you need an absolutely 100% conclusive HIV blood test, have another AgAb test 45 days or more after the exposure; if you do so, you can count on another negative result.

You could try an over-the-counter anti fungal cream for your armpit inflammation; the same products that work for athlete's foot or jock itch will be effective, if your self-diagnosis is correct. But see a doctor for further advice if that doesn't take care of it.

I hope these comments are helpful. Let me know if anything isn't clear.

HHH, MD

 So I had a doubt about that. Then  I did some more research and I think they use roche cobas?

That concludes this thread. I hope the discussion has been helpful. Best wishes and stay safe.