OK, I said I was never going to be one of those people who gets on the computer and asks if I have a medical emergency, and here I am
Fletcher got up about 1:30 and went outside. When he didn't come back in, I got up to check on him, and he seemed fine, just wanted to play. I went back to bed, but when he still didn't come lie down (they sleep on dog beds in the bedroom), I got up again, and he was just throwing up in the living room. It's now around 2. He threw up his dinner, and the poop he had obviously just eaten . While I was cleaning that up, he threw up twice more, the last time just a little clear stuff. His abdomen is not distended or hard, but he is still pacing, whining and panting, clearly doesn't feel well.
OK, I just checked on him, he jumped up on the couch and stopped panting, but still doesn't feel well. I am inclined to keep an eye on him, and wait, but should I take him in?
OK, editing to add, he's now lying on his bed looking at me like, why are you up? Let's go to bed! So I guess the crisis is over, but if anyone has any ideas about what caused all this, I'd be glad to hear them.