I had sex with an unknown person, someone I met online. We used a condom that did not slip off or anything, just gave me a bit of irritation, I wonder if either the condom or the lubricant irritated my anus (can lubricants r condoms cause irritation?). I tested for HIV at 5 weeks and 3 days and the test came back as NON-REACTIVE (Negative)...so my question is: Should I test again? Should I be worried? Please help.