Endometriosis or pcos

My whole life I have had heavy periods going through a super tampon on hour having 7-9 day periods at times I would go months without getting a period and this has gone on since I was 13. I was on  birth control for a long time and that got it under control but I stopped taking it a year ago when I got pregnant and miscarried while on the pill.  I started using glow in July and this is how my periods have been and I haven't had a period since November and I tested for pregnancy in early December and it was negative what could be going on ?