Anyone with thyroid disorder here?

Arie

I have Graves’ disease and hyperthyroidism I’m now taking synthroid after getting my thyroid removed. My period have always been normal until last month when it lasted 24 days. I went to two different gyno and they told me nothing was abnormal with me after running some test. This month my period is now 8 days late. I took a pregnancy test and I’m not pregnant. I don’t really know what’s going on. Has anyone ever experienced this? I’m not on any birth control btw