Pretty unusual for a person with an "overweight" problem to be hyperthyroid. Perhaps they, said or meant to say "hypothyroid" meaning an underactive thyroid gland. which is not uncommonly associated with weight gain.
One of the thyoid function studies known as "TSH" goes UP when your thyroid function goes DOWN. Maybe that is the one that was elevated!. Since you have had your tests done again, hopefully things will make more sense soon