Suggest Treatment For Severe Pain In The Index Finger

I use a right handed 2 button mouse with a scroll wheel and typically use the index finger for the left click button, the middle finger for the scroll wheel, and the 4th finger for the right click button. My index finger usually hurts by mid week from frequent activity. The pain in my right hand index finger is between the 1st and 2nd joint (nearest the palm) and runs along the outside part of the finger, on the side adjacent to my thumb. I had a cortisone shot with physical therapy for this condition about 14 years ago and now it s just a chronic condition that I rest by switching hands (I think the doctor or the therapist referred to it as computer mouse finger or something like that). Now, my 4th finger has begun to hurt but in a different location. The pain in the right hand 4th finger runs along the same side, but it s located from the last joint to the fingertip. Coincidentally (or possibly not?), my right elbow is also sore near the outside but I don t feel any inflamed bursa. I rest my elbow on the desk while using the mouse. Do you think both the finger joint soreness and elbow soreness are related? How can I check if it s just a bad ergonomic posture or if it s something else?