Miscarriage??

I was just wondering if any of you that have had a miscarriage could tell me if maybe I am having one?

I was on birth control, but wasn’t taking it correctly because I accidentally missed days so it was most likely in affective.

I have extremely heavy bleeding with lots of large clots and cramps that switch back and forth on which side is cramping. The cramps are so painful that I pretty much fall to my knees and want to cry. I haven’t bled this heavy in years. I fill pads pretty quickly. I change them every 2 hours almost.

I’m pretty sure a pregnancy test would be negative by now.