I have been having a terrible time with concentration. Its not distraction, just feeling stuck. Come to work, stare at computer, try to part the fog and work, not too productive...etc.
This is not a solution, just a temporary fix. . . but I find that if I watch Hoarders, I get so grossed out that I work like a demon for a short while afterwards! (Dumb but true).
It's frustrating that workplace culture treats us as machines that are expected to have constant output when we have good days and bad days. I hope things improve for you.
Vitamin deficiencies can cause concentration problems - maybe we all need some vitamins! Are you taking any? I know for me, a lot of it is just that I'm in pain or uncomfortable, and it's just so hard to get past that. Probably the same for you!