So my PCOS... Isn't PCOS

I recently found out that I might not have PCOS. They're telling me that I might have subclinical hyperthyroidism. The doctor tells me that my levels aren't high enough to classify as hyperthyroidism, but it would explain why the only symptom I have is super irregular periods. Has anyone experienced this before? If so, has the medication helped you ovulate and gain your period back? Any input helps 😊
Update: So it's subclinical hypothyroidism (TSH 3.6) it's not that high, but it's been hovering around there for about a year. I'm going to be put on a very low dose of synthroid. We'll see if this regulates my period and leads to ovulation. It's been 6 months since my last period and almost a year since I got off BC