What is the window period fir HIV test? I have done provera DNA test on 11th & 17th exposure result was not detected. I have also done 4th generation duo test on 28th 35th and 45th days result was non reactive .still having symptoms from 20th days flu, dry cough, swollen lymph node on both neck, body pain minor body itching. My exposure was lip blood of prostitute with my lips & protected sex (no breakage or slippage of condom. please guide.