I had this.

It was diagnosed as tendonitis. Almost similar to Carpel Tunnel, but with the outer wrist joint pinching the tendon running down my pinkie.

Cause: Poor playing technique with right hand.

Remedy: REST FOR TWO-THREE WEEKS. Then change your playing technique so that (my) hand is ALWAYS perpendicular with the keyboard. This is not as easy as it sounds since I've had this poor habit of torquing my hand to the right in order to finger chords. My teacher drilled me to no end to get me to use correct fingering with my hands using my 3rd, 4th, and 5th fingers more.

I have not had any pain since I corrected this behavior!!!!!

Now this may not be your exact diagnosis Scott, but in my case I did have pain, numbness, and tingling in my fingers.

Please consult a doctor and even a Piano teach to evaluate your technique.

Al