You might have noticed that one of the stats I regularly supply is the type of day I am having. There are three types of days in this context. A good day, an ok day, and a bad day.
A good day is a day where I am in minimal pain and unlikely to bring on more pain by carefully doing stuff.
An ok day is a day when I am in some pain. I can still function and, if I am careful, I might feel better later.
A bad day is when I am in crippling pain and can do nothing at all. Bad days are the ones that have been responsible for redefining what a 10 on the pain scale is.

