What Causes Abdominal Cramps Followed By Abnormal Menstrual Bleeding?

Hi I was due a period but never had it and instead I had a pain in my uterus area which was very painful and tender, i was very bloated and my stomach was rock hard. I had this for 4-5 days without any bleeding. However, once the pain had stopped, almost immediately I started bleeding lightly and have been for everyday for four weeks. My question is could it have been a burst ovarian cyst (I have endometriosis) and could that have affected my hormones to make me bleed every day? Thank you