Metformin

So I was told I didn’t have PCOS just cystic ovaries and was put on metformin to help decrease that I guess. Been taking it since October, but since December my periods have been so out of whack it’s strange. I get really nauseated and throw up now 🙄 which I haven’t done in like 12 years! And now I cramp so badly and then the other day when this cycle started I felt a lot of pressure. I was scared something was going to come out of me but it was just a bunch of clots. Is this normal or is it something else going on that I don’t know anything about? I have a follow up visit with my GYN at the end of the month since starting the Metformin but it’s a long way away!