Saturday, I thought I had a bug. By Sunday it was clearly an injury. Something abdominal: if I had a left-handed appendix, somewhere around there. I'm okay as long as I keep reasonably still, and I'm okay walking around; but standing up, sitting down, leaning forward, bending over, lifting - these are all horribly ouchie.
Obviously I am going to live with it another day or two before I even pretend that I'm thinking about going to see a doctor.