My period is a week late. The last time I had sex was early October, I have had my period since. is there any way I could be pregnant?

My period was due last Sunday. It is currently a week from that & still no period. the last time I had sex was October 3rd & I got my period October 22nd. It lasted 22-25th & I was projected to start my next one November 16th (last Sunday) .. There is no possible way I could be pregnant right ? what is going on my period is never this late!! I do work out but that isn't anything new, I have been working out for almost three months now. is there something wrong with me?