Period was 6 months late..found i have 2mm ovarian cyst and have been bleeding for past month+ with big sized blood clots any idea why? thank you inad

The most likely: Reason is irregular ovulation. Without cyclic changes in hormones estrogen is steadily produces causing growth of, then falling away of, the uterine lining. A 2mm cyst is barely detectable, sure not 6 cm? In any event, look up pcos. Do not despair if this is the problem; short term consider pill to prevent anemia. There are many good tx for pcos (see metformin) if that is the case. Gd luc.