plan b

Ok so I had unprotected sex on the last day of my period November 28. He didn't finish inside of me.. It was outside but near my vagina. So I took the plan b pill the 29th just in case. And on December 5 I got what seemed like my period. I've taken the plan b before and I remember that I'll have a period right after. I'm due for my period December 24.. Should I be worried? I have very sensitive nipples right now, did anyone get a symptom of sensitive nipples dues to the plan b pill? Please be nice!