Tennis Elbow and Golfers Elbow are almost always just repetitive stress with bad posture, ie: musculature imbalance.

If you're on the computer, look into keyboards that are ergonomic. Fix your posture. I had this and fully recovered and wound up with TOS a year and a half later because i never fixed my shoulder posture which probably predisposed me to getting an elbow RSI in the first place.

Remedies that work:
Heat and Ice.
Ice bath (fill a sink or a 5gallon bucket with ice). Ice your entire forearm. In the beginning i would just try a lot of icing to remove inflammation, and within a day or 3 start alternating between ice, and heat. You can fill a bath, or the second sink, with hot water, and just roate back and forth every minute or 3. this moves blood in and out.
You can have really cold and really hot, or you can have cold-ish and kinda-hot. I prefer colder to ensure that im really pushing the blood out.

Blood in this case is getting trapped in these muscles that are possibly full of scar tissue. Trapped blood means not enough oxygen can get in, and the trapped blood is full of pain receptors. Pushing that blood out will allow healing to begin.

This is fairly conservative, youll need to address the tissue too.

Grastons and ART
Find a sports chiropractor or someone who can perform this on you. It's not that painful. They will just rake your injury with instruments to break up scar tissue.

Trigger Points
Trigger points in your forearm, upper arm, and shoulder, can exacerbate this. Get a la crosse ball, and either put it in a long sock or just use it directly on the wall and find tender areas and work them out.
The Trigger Point Workbook by claire davies is a great place to start.

I had a tendinosis of the elbow and needed to use all 3 of these modalities to get better, but the recovery was relatively quick when i was able to find a good chiro with Grastons.