Miscarraige maybe? Tmi no pic

Christina • Married 9 years in June. I am a maternity and newborn photographer and have struggle with infertility
I think I may be having one but I need some advice. I was 4 days late which i never am and had terrible cramps for about 8 days before my period started. Well she showed her face and i hurt so bad i can hardly move. Last night at like 730ish i passed a huge clot. (Ive had them before but always small this one was different.) and ever since i did that ive been bleeding really bad, do you guys think thats what it could be? Im scared it is i never tested bc i didnt want to get my hopes up after so much disappointment.