see the doc for sure, and when you finish a pitch, always finish with your arm rag loose. the hand should finish on the glove hand side of the body above the belt. this is called cushioning the elbow. let it come around and even hit your rib cage on the glove side as it slows down. this gives it a chance to slow down over a longer space (decelleration) instead of stopping in front of you and sending a recoil shock back into the elbow and shoulder.
pedro will slap himself in the back on the glove hand side of his back with his throwing hand after releasing a good fastball. it is incredible.