do you have pernicious anemia? pernicious anemia and thyroid issues tend to occur together. i'd ask the doc run blood tests...tsh, ft3, ft4, and THYROID ANTIBODIES (antithyroglogulin, antiTPO, etc).
Although it is the most widely used, TSH is not a very definitive test for hypothyroidism. It does not correlate very well with thyroid related symptoms, including metabolism, fatigue, etc. I suggest that you request your doctor to test for free T3 (FT3) and free T4 (FT4), along with the TSH. FT3 is the most active part of thyroid hormone. It is 4 times as potent as T4. If you do have hypothyroidism, you should know that Forum members seem to have the best result when their doctor treats them by listening to symptoms and regulating their FT3 and FT4 levels to alleviate their symptoms, not by TSH.