I had a hemi thyroidectomy (right side) because i had a tumor. shouldn't i be on medication if now the left one is enlarged and overcompensating ? i

Need Blood Test/ultr: You need a ultrasound and tsh, freet4, T3 (liothyronine) levels and you may or may not need a boipsy of the left lobe of thyroid to find the proper treatment consult your endocrinologist if you have not done so.

Benign or not?: If the tumor was malignant, the whole thyroid should be removed. If not, then no replacement thyroid is needed.