I had unprotected sex exactly 2 weeks ago. My boyfriend didn't ejaculate inside of me but I took plan b because I was scared of precm. I was supposed to get my period a week after (last week) and I still haven't gotten it. I was on birth control (patch) for about a year and I stopped last month because we were taking a break. So I thought maybe I wasn't going to get my period the same day I used too and I also know that plan b could delay periods so I didn't worry much until now that I've seen a light brown discharge and I heard it could be from implantation. Is there any chance I can be pregnant?