I developed hyperthyroidism after tx too. It was picked up on my six month checkup. I was put on medication to slow it down. I'm not sure if it has anything to do with the Hep C treatment because it runs in my family.
I dont know that you developed it because of treatment because quite honestly I would hope that your doctor would have caught it back then, running Endo tests is a regular part of treatment.
I have hypo from treatment but it happened way back when I was on it and I take Synthroid every day to control it. If you had developed it on tx it might have gone away afterwards but now two years later I'm not sure it could even be connected in any way.
You need to see an edocronologist to take care of this.