when my Dr. first put me on 100 levothyroxin I don't know if it was because the dose was to high, I had a lot of reaction to it. So I had changed to levoxyl and I still had weird reaction, like leg twitching at night, just one leg, and it really twitched, not just slight twitching. And I had odd feelings mentally, so now I'm on Nature Throid and doing real well, no real problems
You could be either overmedicated or need to change meds. TSH is very low. Do you have FT3 and FT4 with reference ranges to post?
How much Synthroid do you take?