[Coffee.]

A lot of times, caffeine will affect my body (jitters) but not my mind at all. I've literally drank a double shot of espresso coffee, and been able to go to bed within that hour. You may have become partially immune to the caffeine if you've drank a lot of it in high quantities.

I would wait for the results of your doctor. I would also try sleeping more, and maybe if you can afford it, participating in a sleep study! There may be something going on with you not getting a restful amount of sleep. Good luck!