Just started my midodrine for dysautonomia. When I feel my pulse I can't feel it as much is this from vasoconstriction? I feel better!

Yes. Midodrine causes stimulation of the adrenergic receptors, causing vascular constriction and increased blood pressure. It is particularly useful when used before eating, or before standing for prolonged periods. Just curious - did you try Florinef (fludrocortisone) first?