@LucH thank you for that. I have also been taking low dose b- complex, but it prob doesn't have enough b2. I find supplementing the b vitamins to be so complex, with so many pitfalls. You need x to make y work, but if you take too much x, it will deplete z etc etc. It's an endless minefield.
I'm going to just work on thyroid and diet, and try and get enough b vitamins from milk and liver. Even if I don't fix all my issues, I should still make real progress.