It can be a great mystery. This thing we call Graves’ disease. Have the doctors considered that what may be "normal" thyroid levels, may not be normal for you?
To get a normal range they take a large set of tests, some high and some low, to come up with an average. I tested in the "normal" range for years and felt much as you did. My doctor finally upped my thyroid levels to read at the "high normal" rates and I felt much better. Now running high normal causes other problems that need to be addressed. Such as increase bone loss and muscle mass loss.
But you may have been a high normal when you came down with Graves’ disease and now they are running you in the normal range which may be low for "you".
It does not hurt to talk to your doctor about this. Also ask how you body is converting T3 to T4. Some people do not covert well and may show a normal reading when their T$ is actually low. The doctors need to run a full thyroid panel, not just TSH which some insurance companies think is sufficent.
Jake George
On-line Facilitator