4. Hyperactivity
Too much T3 and T4 will burn weight by accelerating the metabolism as mentioned. But remember, weight loss occurs when the body burns calories for energy and as such, you can also expect to experience increased energy levels and possibly hyperactivity.
This could be associated with bipolar depression (mania) or ADHD but if it occurs alongside trembling and weight loss, then you may want to look into whether a thyroid issue is responsible.
Go to see your doctor and get tested!