Agreed; I've worked hard to prioritize sleep in my life, though not to the extent that the parent poster has. But simply stopping, right now, and going to sleep for as long as you need, at the first sign of illness, will save you days of misery.

Every single time I've said "well, I'll just go into the office and if I don't feel well, I can just head home midday", I've regretted it. It's too late.