Cramping would be the pregnancy. I have pcos and if I ever felt anything (which was rarely) I could tell the difference from uterine cramps and ovary cramps. Ovary cramps are more on the side and they don't "cramp" really, they burst which can be pretty painful. And it's not gonna effect your pregnancy at all now that you are pregnant. And they can't really do anything besides do surgery to remove it but unless you have issues getting pregnant they'll wanna do meds first before surgery. Both unnecessary once pregnant
Is it the corpus lutem cyst? That is normal from what I was told and a sign of healthy pregnancy. I had cramping early on. Sometimes felt like someone had a hold of my ovaries and was squeezing. Contact your ob to be sure if you are worried