I do hope the back pain fades away soon -- though I am actually rather jealous that you get to stay in bed listening to Bach and reading the Baroque Cycle!

Re your body misbehaving only once you're off work: I used to get this a lot when I worked in the City. Cold- and germ-free for months, then they'd all hit at once on my way to the airport and sunnier climes. I think it's a work ethic / stress thing.

And I suspect I now have the opposite: my cold didn't kick in until I'd started werk ...