You have extreme hypothyroid symptoms, but we can't tell why until we have more info.
Your FT4 is fine - your thyroid is producing enough of it, yet your pituitary is still screaming for more. You are probably (emphasize probably, not certainly) converting a lot of it to Reverse T3. You need to test FT3
Are you paying out of pocket or through health insurance? Basically, how many tests can you afford?
-Cortisol (8am blood draw)
You will PROBABLY also need:
-Thyroid Antibodies (TPO/ATA)
Tests I also strongly recommend and are needed to rule out some potential causes:
-Vit D, 25-hydroxy
These tests are IMO all necessary, but ordered by importance in case funds are an issue. The more info we have, the more we can help. I personally wouldn't suggest medicating until the problem is further defined. It might help or it might not.
The bottom line is you have every hypothyroid symptom in the book despite the fact your thyroid is producing normally. Something is wrong.
Also, feel your throat carefully and check for lumps. A small lump could be an early stage goiter.