I take a fourth generation test combo at the 25 day with 0.21 no reactive, and at the 28 day another with a result of 0.18 no reactive result, and at the 33 day a third generation test with a no reactive result. At this point, Statistically speaking, how reliable are these results ?. 95%? is ther a chance of a late seroconversion?. By the way, every syntom I read, I have it at the next day, but I think that is in my head. I am really worried, please healp me. My experience was have protected sex with a prostitute. I know that is not a real risk, but I really worried for my syntoms.