Implantation bleeding is very light…pink/brown for a couple days or even longer than a week (that happened to me). It’s not like a regular period which is a lot of bright red for a couple days. All women are different though. I’m sure you know what your regular period is like. If your bf didn’t cum, there is a low chance you could be pregnant. Since you got some bleeding either a period or implantation, the best thing to do is take a test since this is the right time to do it.