Have you had thyroid antibodies tested? You could have either Hashimoto's or Graves Disease, but you can't know without proper testing. While Hashimoto's is, typically, associated with hypothyroidism, it's often characterized by periods of hyperthyroidism in the early stages. Graves Disease is always associated with hyperthyroidism.
To test for Hashimoto's, you need Thyroid Peroxidase Antibodies (TPOab) and Thyroglobulin Antibodies (TGab). You need them both, since some of us have one or the other, some have both. If you have only one, you run the risk of misdiagnosis.
While some, with Graves Disease can have TPOab, the definitive test to confirm/rule it out is Thyroid Stimulating Immunoglobulin (TSI).
When you get the tests results, please post them and be sure to include reference ranges, which vary lab to lab and have to come from your own report.
I think your levels will help answer a lot of your questions and help guide you and your doctor with a game plan. Keep us posted!
C~
I was hyperthyroid for a year and my poor appetite never improved and I lost no weight either on the scales (although I have muscle atrophy). The reason was due to severe insulin resistance which worsened even further due to excess thyroid hormone.