Help pleasee

So I’m on the pill, and I didn’t miss any days I was a couple hours late on I think two of them though. So this week I was supposed to get my period but there’s practically nothing coming out. I had a tampon in and it seemed to have a little more, but it’s only really brown blood. I did just recently skip one of my periods, but that was two months ago so could this just be due to that? I’m just nervous what I’m experiencing is implantation bleeding. Any other explanations?