Missed period?!!!

So sept 4 I had unprotected sex and a day later I took plan b, . & it was my 4th day ovulating. Couple days later which is Saturday me and my BF had multiple sessions in that 30 minutes time frame period.. We did 2-3 minutes and stop and do it again and so on. Fast forward he peed before our first intercourse but never came..

Today is my expected period but it never came and I'm having major headache and nauseous. Did the plan b delayed my ovulation tho?

I took a test today and it both said negative from different brands.. Should I worry? Please help in scared.. I know I should've been more careful I learned my lesson but please I need advice.