Period or miscarriage?

So my periods are always really heavy but normally not the first day. I haven't done anything different recently to change my cycle or anything. My husband and I have sex unprotected but he pulls out so not trying but not being safe either. Anyways today i started and right away it was heavy. Like i didn't even know i had it until i went to the bathroom and was bleeding a lot. I have taking tylenol like i normally do and it hasnt helped and used my heating pad and also hasn't helped and ive just beem having extreme cramps and quite a bit of clots. Do you think its a miscarriage without knowing i was pregnant or just really heavy?