I woke up yesterday morning with a slight sore throat. If I weren't on leave, and I had to go to work, I would have sucked on a cough drop, drunk hot tea instead of hot cocoa for breakfast, and gone off to the job with no hesitation.
Instead, because I could, I spent the whole day doing pretty much nothing, indulging my need to "rest." That means I read, watched television, drank lots of tea, and generally lay around on the couch.
Maybe I won't get sicker because I took the time, or maybe I would never have gotten sicker no matter what. I'll never know. But it was good to have the chance to relax.
Relax when you need to, if you can.