Am I Pregnant? Helppp

I am on the pill, and I’ll admit I forget to take it once in a while. I started “spotting” a few days ago and it was small amounts, but noticeable and lasted three days, and then my birth control pack ended which meant my period should begin and then yesterday I had the heaviest day I’ve ever experienced and I had the biggest clot on the pad. It was huge, and dark red which started to send alarms through my head. and now today I have almost no bleeding. Any ideas what is wrong? I’m freaking out!!! I’m not sure if maybe I am pregnant or miscarrying or if my birth control is at fault.