It seems to be worse in my left hand and specifically in the index and middle fingers, but I have to say this is a very subjective judgment. My hands seem to have a pinkish caste to them.

I spent over 30 years as a professional tech writer (please don't abuse me for your terrible manuals and guides, it ain't my fault). In all the places I worked I pestered managers to give me an ergo working setup. I made a thorough study of ergonomics and invented a quality wrist rest and manufactured them for a while in my garage.

I use a Logitech Revolution mouse, which I think is well designed. It fits the hand very nicely.

Now I am retired, I may actually spend more time at the keyboard compiling research and writing freelance articles than I did as a tech writer. I would have had breaks away from the keyboard to attend meetings, work in the lab and do other things not associated with text entry or research.

So, yes it could be related to my computer use. So far as I know, my setup would pass ergo inspection, but ironically I don't have one of my own wrist rests because of short sightedness. There is a box of them stored in San Diego in my storage locker.