you need further testing. You need to get tested at 3 months from the last encounter for it to be conclusive. But since you were tested after 6 weeks and it came back negative, you have a very good indication of your status. I know you are scared right now but take a deep breathe. I do not think there is a documented case of someone changing after their 6 week test. I know you are going through a lot of anxiety right now so if you do need someone to talk to shoot me an email.