I recently was told that after some testing I have parthesia, issues with my sympathetic and parasympathetic system. Which explains most of my symptoms but I am getting this extreme internal flash of heat all over my body. It went away for the first time like two days ago but now it’s back. It’s been constant for well over a few months. I also have extreme brain fog, blurry vision, gastro issues and gait problems including freezing gate. My neurologist says no signs of Parkinson’s, and all my physician could say is I don’t know .