Have them do a complete thyroid function test. This is like 10-11 different things they check. I had low NORMAL TSH but hypothyroid symptoms for a year and a half. They kept saying that I couldn't be having these symptoms because my TSH was normal. When they did the full thyroid function test, 7 of the 10 numbers were off. The worse one was the reverse T3. I was suffering from a thyroid conversion syndrome. I am now taking a natural thyroid supplement for this along with my Synthroid and my TSH yesterday was 1.38 which is perfect. My symptoms are gone and it only took 4 months to fix!!