“What are the symptoms of a low TSH level?”

Weight gain, cold intolerance, fatigue, dry skin, constipation, fogginess.

There are many symptoms of low thyroid (hypothyroidism). Thyroid hormone (thyroxine) is the hormone that keeps things going (stokes the furnace) so the symptoms of low thyroid are that every organ slows down. I will list here only a few of the main symptoms: the heart slows down & loses the strength to pump blood (that causes congestive heart failure), puffy face & legs, dry scally skin, problems of the mind such as slow decision making & learning and even hallucinations, fatigue & slow movements, slow speech and a deep voice due to swelling of the vocal cords, etc. Get the point everything slows down. If this continues & is not treated, it can be fatal from damage to the heart. If things are slowing for you, see a Dr. right away. Hypothyroid can be diagnoses with a simple blood test and can be treated with all functions returning to normal.

A low thyroid stimulating hormone means that you have a high level of thyroid hormone in your blood. Symptoms would likely be high heart rate anxiety and weight loss. See your internal medicine doctor