Rocking habits and twitching

Okay now i consider myself a pretty normal person but my friends tell me otherwise haha...anyway while im doing normal stuff like washing the dishes walking the dog etc.i twitch alot like my eyes,arms,legs start to shake for no reason at all and i only stop when someone tells me that i am doing it.Also i like playing the violin and piano blah blah blah or just reading but when ever i sit or am stressing very bad over something i rock back and forth like um an old person in a rocking chair in fact im freaking rocking right now damnit.

is this normal?