One month ago, I had an unprotected vaginal sex with a girl(a student).Now, she broke up with her previous boyfriend just 6 months ago.After the act, I got worried and ask her to get tested because I never had any sexual encounter with any girl before...kinda like a virgin.So, she told me that last time she had sex with her ex was like 4 months ago...and she tested for HIV through the rapid test at a private clinic.The report came out negative but both of us are not very confident about it.So, we have decided to test again at 6 month mark after the possible considered risk.But we are tensed in the meantime, seriously affecting our works and studies. I have a question in my mind but has been unable to find any absolute answer so far.The question is:1) What is the most conclusive window period at which the results of a HIV test can be concluded as very correct and the need for any further tests can be ignored?2)Supposedly if a person tests for a rapid antibody HIV test and comes out negative 4 months and2 weeks (18 weeks=134 days),can he be sure that he is indeed negative?