Yesterday I bled pretty heavy, it didn't flow or anything, and the next time I went to the bathroom there wasn't any blood. What could this be? It isn't IB, I haven't ovulated yet. The opk I took this morning looks like I might O today or tomorrow. Could it be a cyst bursting? It was followed with cramping and back pain. (BTW I do have PCOS and only a couple of cysts, not a whole lot)