Should I be worried??

So I started my period today (as predicted) and when I first woke up it was a normal amount of bleeding for my first day. I put a tampon in and took it out a couple hours ago, but since then I’ve not really even bled, mostly just a little bit of brown discharge. I fooled around with my boyfriend last weekend, but there’s no way I’m pregnant right? This has to be my period since it’s started on the predicted day?

*Edit: I’m on birth control pills