Just because thyroid related tests are in the so-called "normal" range does not mean they are optimal for you.
In trying to assess a hypothyroid patient's status, the most important consideration is symptoms, followed by tests for the biologically active thyroid hormones, Free T4a nd Free T3. Since hypo patients are so frequently deficient in Vitamin D, B12 and ferritin, those should also be tested.
So please tell us about any symptoms you have. Also, what is your thyroid med and daily dosage. Also, please post your thyroid related tests and reference ranges show on the lab report.
What test was done and what were actual results and reference ranges? Symptoms?
Thyroid gland tissue can regenerate interestingly enough.
So you were on Synthroid for 6 years after the thyroidectomy, correct? Then you had a blood test and levels were normal and you have not taken any thyroid med since?
More important than blood tests, what symptoms do you have, if any?
You really need to know the actual tests, results, and reference ranges shown on the lab report. When you have those, please post here and we will be happy to help interpret results and advise further.