What is going on?..

Ok so this is a bit of a confusing one. My period was due to come on Thursday (8th of April) and my cervix is REALLY high and super soft, I’m 13 dpo (confirmed O with opk’s and BBT) and thought I had a VVVFL on Sunday. but then got a positive oPK this morning but negative HPT. then I started bleeding lightly today. I have really intense cramps only on my left side, which normally with a positive oPK I would put down to O. But I can’t O from my left side as my left ovary was removed back in august. And my normal AF cramps are right across on both sides. What could be going on? xx