My right elbow hurts when i rotate my hand counterclockwise and let my hand sit on a table with my elbow hanging. it also seems to swell. any ideas?

Tendinitis: U need to be examined if your pain persists.Elbow pain w/ pronation as u described could be medial epicondylitis ("golfer's elbow"). Seen also in people who weight lift and in many other activities.Usually the elbow is tender to touch on the 'inside bump'( medial epicondyle).Try a NSAID ( ibuprofen) for a few days . If not improved see your md for exam