Rough sex or implantation?

Hi - my boyfriend and I try our very best to have safe sex, but accidents happen. Anyways, I had to take a Plan B in mid September. I was not on birth control at the moment. I started birth control last week because I had my insurance fixed. I've heard about implentation as I was getting nervous, I've read the direction about the side affects of Errin etc, as I have sore and tender breasts, headaches, nausea at times but that didn't start until around I started BC. Now, my SO had some rough sex(Saturday)and I told him to slow down and he did. Shortly after I went pee and surprised to find blood on the toilet paper but only when I wiped. It wasent dark, more so orange, pink and red combo, but a good amount(but only twice when I wiped). My predicted period is this Saturday. Is this implentation? Rough sex blood? Or the pill? Appreciate kind words back. Thank you.