Abnormal Period

So, around this time last year- I started with these bizarre periods. They were more frequent, with dark blood- sometimes brown, lots of clots.. sometimes I had sharp pelvic pain. I went to the GYN- had a pelvic ultrasound and nothing. Went to an endocrinologist to check my hormones and not a thing. These periods went on for about 4 months.

This month, it’s back again. Dark, clotted blood- sometimes brown. Not super heavy. Some cramping, and 21 days after the start of my last period.

Anyone without a PHD have any ideas or ever experience anything simular?

I’m 32 and have a two year old.