I have central hypothyroidism - my TSH is .0008.
Yours is low, but still eeking out in the range. I used to feel better when I was low TSH, and higher in the range on everything else.
Did the doc do any antibody tests - like Hashimoto's?
Are you on any thyroid meds?
So the doc ran prolactin, a common pituitary thing, and one cortisol test in the morning I assume, which can tell you something, but eh, not much... but he skipped growth hormone which would be the first to go in head trauma (GH, IGF-1 testing - any of that?), no ACTH which would go with the cortisol, and no estradiol, testosterone, dhea sulfate... in other words, you need to go see an endocrinologist and get more testing.
Hormonal testing is a challenge - it has to be done right.
oh I forgot to mention my cortisol (am) was 11 (4-22)