Can Overactive Thyroid Make You Feel Sick
The system slow-down caused by an underactive thyroid means less energy is being burned by cells. Less energy equals less heat. On the other hand, an overactive thyroid puts energy-producing cells... You mentioned too much thyroid- that's what makes thyroid the devil. The symptoms are almost identical to low thyroid-fatigue, dry skin, thin hair, nervous, moody, depressed, etc.
The main difference is that your blood pressure goes up and damages your heart from beating too fast and does a job on your kidneys. Hyperthyroidism