HI, thanks for using healthcare magic
It is possible that it may need repeating if you doubt that it is correct. At the same time the thyroid
hormone levels should also be done with the TSH
If you are concerned about general pituitary failure then there are other hormones that can be tested but in most cases, symptoms would be present.
The TSH is , as you indicated, released from the pituitary and controls release of the thyroid hormone from the thyroid gland.
A high TSH usually means that the level of thyroid hormones in the body are low, this is the reason that you would need the actual thyroid hormones levels checked.
If the value is accurate and thyroid hormone level is low, then you would need the dose of the synthroid
I hope this helps