Unfortunately, I think I know exactly what you're talking about.It's, for me, a kind of intramusucular aching which is omnipresent, and in odd places where there aren't corresponding joints.No, I don't think you can solve it, and I doubt it has to do with your technique at the keyboard. Just one of those things. I use ibuprofen in an attempt to combat inflammation, but at maximum prescribed strength, over a regimen of months, it's not been successful entirely.
Not a virus but I am going through a tough time, personally. I hold a lot of tension from stress in my body, so it's possible that my muscles are tense and the resultant lack of flexibility caused this problem. Idk.
It seems like it's a forearm flexor issue because I notice the tension/ache when I close my hand (without my fingers curled). I also notice it when I grasp something like a tea kettle and carry it in a way that requires grip strength. The ache is in the same spot.