Pregnancy

Me and my boyfriend had sex two days after my period ended , he came inside me . I'm not on any birth control nor have I been for over two years . Almost two weeks later I had some spotting for a few days . It was off and on . My period is now late by a week , I've tested twice but both have been negative . I tested the day I was supposed to start and the day before I was supposed to start . What does this mean ?