I"ve also been 109 lbs for the last 10 years and over the last 3 months I've lost 4 pounds... it's affecting my health
Can you post actual thyroid related test results, along with their reference ranges, which vary lab to lab and must come from your own report? Have you been diagnosed with an actual thyroid condition? If so, which one?
The endo will review all of the blood work, and other tests, possibly order some more, then make a determination as to the next step.
We can't really make any assessment, without seeing actual labs and test results.
Toxic goiter comes to mind. Hypethyroidism/Graves.
I am sure your Endo will check into that..