Why Do My Hands Get Sweaty, Tingly, And Why Do I Tap My Foot, Scratch My Scalp, And Shake When I M Nervous?

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.