Freaking out! Help

I posted a few days ago about how I had sex but he pulled out. I'm on the birth control pill and take it perfect but sometime in the week and a half leading upto the sex, I had missed a pill and doubled up the next day at my usual time. I was 100% taking the pill for at least 4 or 5 days before sex and continued taking it at my usual time since. It's been a week since we had sex and a few times today I've had random pink spotting when I wipe. I havent spotted or bled at all on this pill since the first month and I'm now a week into my 4th packet. Could this possibly be implantation bleeding? Or just random spotting from maybe missing the pill or taking one a little late or something? About 2 days ago I did take my pill late (but still within the 12 hours the pamphlet says). I hadn't thought about it much and assumed I'd be okay considering he pulled out aswell as probably still being protected but this spotting is throwing me off.