...painful. It didn't go away even when I stopped playing racquetball for a month. It did go away after two weeks off for Christmas vacation

It turns out that the actual problem was not caused by racquetball. It was caused by my index finger clicking my mouse because my mouse was not at the proper elevation. I fixed that at the tennis elbow went away.

As others have mentioned, a compression band on my forearm also helped a lot in the meantime. It was giving the tendon in my index finger some pressure and taking the pressure off from where that tendon connects in the elbow. Pressing on that tendon in my elbow was causing sharp pain while I was experiencing tennis elbow.