Struggling through NaNo with Back Pain

I certainly did not need this most recent flare up of severe muscle spasms in my lower back right now. I've been plugging away at my NaNo novel and am about two thirds done but sitting anywhere in my house to write is agonizing! Like work, I do not have an ergonomic chair...no chair with any sort of back support at all in my home. I am used to writing in the ladderback Hitchcock chairs in the kitchen, but I am struggling with that.

If you hear screaming coming from my house it's only me- frustrated and in pain, ranting against the injustice of age, RA, and the insults they have thrown across my path since I woke up in agony on Sunday morning! I've missed two days of work so far ad three days of NaNo writing to the extent I was hoping I would be able to write.

I don't get depressed about episodes of health issue flare-ups, I get angry and just need to vent about the things I cannot control in my life, like back pain and muscle spasm.

And now I will go quietly and do an hour of writing or else I will feel my entire day has been one huge waste of my time.