For now... lots of rest, stretching, avoidance of the activity (or motion) that causes the problem, ice, an "good" brace that will basically give you an new insertion point for the muscle, thereby giving the tendon a rest.
Certain types of soft tissue treatment will be of great benefit... Active Release Techniques, Graston Technique, and Ultrasound should all help.
See your local chiropractor, physiotherapist, athletic therapist for these things.
After the pain is gone, you will want to strengthen the area so that it is less likely to happen again.
For curiosity's sake.... is it the inside of your elbow or the outside?
Medial Epicondylitis is the inside... also known as Golfer's Elbow... involves an overuse of the forearm flexors (wrist and finger flexors).
Lateral Epicondylitis is the outside... Tennis Elbow... involves overuse of the forearm extensors (wrist and finger extensors).
I believe there are a few other threads about this... I'll try to find them.
Cheers!, and best of luck.
Pain In Elbow When I Twist My Forearm
Forearm pain
Elbow pain source???