Thyroid advice!

Hi,
I'm 30w, I have a high heart rate (100bpm) so the doctor sent me for gestational diabetes test, everything fine, so he sent me for an ECG, everything fine, then had to go and get my thyroid tested, even though in the previous blood test everything was fine. Apparently my thyroid levels are fine, but my hormones are low, indicating over active thyroid, but they can't figure out why. No other health issues EVER, none whatsoever in the family. I have another appointment booked for 2 weeks time, so I'm assuming it's nothing major or they would've wanted to see me again right away? Anyway, question is, has anyone dealt with this before? I'm so sick of doing all of this running around- I have an 18 month old, my husband works 14hr days and I have no family or friends here. Every time I go to the hospital I wait at leave 2 and a half hrs before being seen. This morning it was an almost 4 hr wait with a screaming 18 month old. I just feel like I'm doing all this for nothing, when everything keeps indicating I am fine, and the baby is perfect. Anyway, anyone dealt with that kind of thyroid issue before?