Why do i play with my hair all the time?

when im at school i notice i bounce my foot ( i sit cross legged and the foot on the top i like bounce..? idk ) and if i wear flats i take my heel out and pop it back in the shoe..? idk how to describe it. i jiggle my foot and i play with my hair a lot. why do i do this? i don't like anyone... do i have like some type of disorder? i am all ways doing one of these things.