Elbow pain with any movement. feels better by holding it and keeping in next to abdomen. what could be wrong?

Commonest cause is a: Tennis elbow, with pain/tenderness on the outside aspect of the elbow; while the inner aspect pain is also called the golfer's elbow. See your pcp or an orthopod to be properly diagnosed so treatment can be started. Taking pain meds, using a sling to help it rest, will be be helpful, till proper diagnosis is made. Good luck.