Why Do I Experience Sweaty, Tingly Hands, Foot Tapping, Scalp Scratching, Shaking, And Restlessness When I M Nervous, Even At Home Or In Crowds?

I’m a introvert and I’m just trying to figure out why do my hands get sweaty, and tingly when nervous, and I also want to know why I tap my foot and scratch my scalp/head and my neck also when very nervous.Lastly I want to know why I begin to shake and move around when feeling nervous.I just don’t know why I do these things, I do these things in crowded places and even at home a lot.