please help!!!

I am so scared, I am only 17 I know I made a mistake, I had sex without protection nd he came inside me... i panicked and made him buy me plan b a day later, but the day of the incident I was In the middle of my ovulation..... so I don't know if it was effective???? my period is in 10 days yet my boobs hurt so much and I have cramps and lots of discharge! also when can I take a pregnancy test? I Am so terrified I know I should've practiced safe sex. )))):