WordNet sense 1 (a sudden muscle spasm; especially one caused by a nervous condition):

vellication, twitching

WordNet sense 2 (toss with a sharp movement so as to cause to turn over in the air):

flip

WordNet sense 3 (move with abrupt, seemingly uncontrolled motions):

jerk

WordNet sense 4 (squeeze tightly between the fingers):

pinch, squeeze, tweet, twinge