I've tested and gotten negative every time. I plan on testing again but not for a few days. I honestly not stressed about it because not matter what it will be okay and me and my boyfriend have talked about every out come and I'm fine with it. I am on birth control but sometime last month I did miss a pill and I can't remember exactly when it was. We did have sex during my predicted fertile days. If I'm not pregnant is there any serious reason why my period could be late?