Hi and thank yo so much for this query. I am so sorry to hear about your battle with graves diseases and the recent low TSH levels. Yes, excess levels of thyroid hormones intake can explain this. Are you experiencing any signs and symptoms of hyperthyroidism like palpitations, excess sweating, anxiety, heat intolerance , diarrhea etc? If this is the case, then your doctor would most likely consider dropping the dose to find a lower one that keeps the value to TSH in the normal range and symptoms under control. I hope this answers your query and you find it helpful. Please, follow up with your doctor and get the drugs adjusted to address your health problem. I wish you good health.. Dr. Ditah, MD.