so i had sex the day my period ended (no bleeding) it was my first time, so my boyfriend didn't put on any comdom, after we were finish he said he didn't finish inside me but he gave me a Plan B pill and told me to take it just in case... i took it about 3 hours later... now a week has passed and im started to vomit for no reason and when i woke up i saw that i was bleeding... i putted a pad on just incase and it looks like its me period... why am i seeing it so early? is something wrong?