Blueberry, if the tests and treatment for thyroid are not successful, what you describe sounds alot to me like fibromyalgia. I was very fortunate and got diagnosed with it quickly (which in the 90s is amazing) and treated it is not a problem. I was having severe headaches and I was exhausted. The not being able to focus is part of what is called fibrofog. Anyway, it might be just that it's what I'm familiar with but I thought I would throw it out there to consider if what you are trying doesn't help.