I thought, as most artists probably do, "Oh, sweet lord, the tendonitis cometh," and glumly called it a sick day. I spent most of the day bummed, as my faithful appendage, 'pon whom my livelihood relies, had betrayed me. I looked forward to a grim, if distant, future of pain and misery and learning to paint with my left hand. I sulked.
Then, 'long about eight in the evening, I picked up some Chinese food, and my brain went "AHA!" because holding the bag set my arm on fire and I realized--it's not drawing that did it, it's that I'm a moron. The day before, I had gone to the store, and rather than get a cart, I was all macho and picked up a basket. Except that I had about twenty pounds of hardcover books in there from visiting the used book store, and then I got milk and cream and eggs and pasta sauce and frozen crap and the end result was that the basket was insanely heavy to lift, and I really needed both hands, but I made my right arm do it anyway while I wandered aimlessly around the store looking for things I'd forgotten, because I'm an idiot. (I'm not just wussing here, it was really heavy. Who'd've thought two books of Morrocan photography would weigh so MUCH?)
So my faithful limb did not shirk its usual duty, it was rebelling against overuse. It's not the drawing, (although the six hours of painting on top of the strain probably didn't help matters much) it was a one time misery. And I feel much better today, so all is right with the cosmos, and I will be very gentle with my poor abused arm this weekend, and hopefully it will forgive me.
I am just now getting to the age where if I abuse my body, there is a reaction. And I am really not used to that--my body was such a stoic taker of grief in my youth that it's hard to get used to.