I’m feeling discouraged

I was diagnosed with Graves’ disease in 2021 exactly three months after the first time I got COVID. I went into remission with PTU ( allergic to methimazole) in 2022 but that was short lived. I have been on PTU ever since and have been doing ok on it. Labs from August showed I was sub clinical hyperthyroid with all hormones in range other than TSH and even antibody levels have gone down. Just got my labs and ultrasound taken yesterday and everything is messed up. My TSH still is <.01 and now t3 is somewhere around 8 and T4 is around 1.9. My ultrasound showed diffuse increased heterogeneity and intense increased vascularity of the thyroid consistent with thyroiditis which I have never seen before. My endo said the results are fine and don’t need to worry. She hasn’t reviewed my most recent lab tho. I just don’t know what I’m doing wrong. I’ve actually changed my diet to more Whole Foods, I make my lunch and bring it to work as well as dinner. I don’t drink alcohol or smoke and I have been consistent with my PTU. I also recently started going to red light sauna to help with any inflammation AND stopped drinking coffee. So why all of the sudden has it gone so bad??? :(