Hi Worried about it. Thank you for sharing your story and I hope that I am able to put your mind at rest. Using a condom is the most effective way to prevent onward transmission of HIV this is because it is a form of barrier contraception. Using a condom makes these encounters very low risk. I believe you would know if the condom split due to a change in sensation and also the condom would be unlikely to hold the semen once the condom is removed. The accuracy of the BioSURE HIV self test never changes however some people seroconvert later than others (this is why we say a negative test is conclusive after 12 weeks) - at 6 weeks 95% of people have produced the antibodies to HIV however at 12 weeks this increases to 99.9%. I would recommend re-testing at 12 weeks just to put your mind at rest and then you will be able to move on from the incident. I hope this makes sense but please don't hesitate to contact me further. Kindest regards Francesca Bard, BioSure (UK) Ltd