At the time I suggested Sherpa low thyroid, I myself had this problem. I thought that I did not have enough iron. There was a post about low serum iron effect on thyroid - T4 to T3 conversion and T3 delivery slow. I added some iron. I felt slight difference.
Later I added Selenium, Chromium and vanadium, kelp extract and Rosemary to my diet other vitamins (MedCaps T3) and supplements I already had. This made huge difference.
Energy level is back, etc. etc. Even severe emotional stress did not kick me out.
I still do not have adrenaline rushes. I am sweating a lot though. May be because I did not do serious physical ex for about 4 yrs.