Hi, orthostatic tremor is one of my dysautonomia symptoms. Dizzy, weak and feel shaky in big stores also. Have you checked your blood pressure while lying, then sitting, then standing and again after standing several minutes? I have orthostatic hypotension (low bp upon standing) which causes cerebral hypoperfusion (low blood flow to the brain) which causes all sorts of deficits. Maybe check it out. Good luck.