Am I pregnant?

I’m 17 and I’ve been on the BC pill for almost a year now. I take it perfectly and have never missed one. My bf and I usually use condoms but we also do raw and he pulls out way before he cums. I’m worried right now because my period always comes on time but it’s not due for 4-5 days and I have brown discharge. What does that mean?? I’m scared it’s implantation spotting but idk how to tell. I’m crampy and now I feel nauseous. I’m getting really worried. What do u think??😖