Last month me and my boyfriend had unprotected sex and I’m not on any type of birth control . He pulls out when he’s fin to ejaculate and masterbates so I can see it come out , it was a day before my ovulation day this all happened and it was in June. My period was supposed to start July 6th but I’m 6 days late with sore nipples and I tested 4 pregnancy test with BFN. What could it be ?? I’m never late! Help me