Hello everyone!!! New to the site. I've been playing for 30 years now, practice at least 3 hours a day. My ring finger and pinky (on my left hand) go numb after awhile. To say the least, I was very worried. I went to a specialist, turns out i have a pinched nerve near my elbow. I think the discomfort that you are experiancing could be caused by lack of warming up before you practice. I had to warm up every time before i went on stage, or else i couldnt play our intire set whithout having to take a rest. Thank God for drum solos!!!! It is VERY important to warm up both hands, even before practice. Im sure if you search the web, you can find some very cool warm up exercises. I use scales to warm up, and vary them up and down the entire length of the fretboard. It also helps in learning different scales and modes.
-Shawn Smith