Thanks, all. Here's a picture of Cooper. I'm still very worried. I screwed up last night. I've been leaving the dog door available, but it turns out Cooper is happy to go out, but then balks at coming in. He's never scratched the door or anything useful when he wants to come in; he just sits there silently. So my dog who has a fever was stuck outside for probably half an hour in very low temperatures, in the snow, until I realized he was out there. I was busy cooking chicken for him at the time ... then I fed him some treats that he was willing to keep eating, so I scattered a few more and a few more and gave him some cheese even past when he was kinda like "ehh mom, I don't need any more" ... and yeah, he puked it all up, plus the peanut butter his antibiotics were stuffed into =/ they were dissolved, but I don't know if any got into his system.
He's so skinny =/ And when he goes outside even just to potty, he shivers for minutes afterwards. That's never been the case. And when I put a blanket on him, he puts up with it.
So, no more dog door for now. They get a door(wo)man.
This morning, he didn't want to eat his antibiotics stuffed in peanut butter. I pried his jaws open and shoved the peanut butter in, and he did eat it from there. Felt awful, but I had to get them in him. Then for breakfast, I just gave him a few chunks of chicken breast and broth, which he did eat.
Yesterday afternoon, we made a lot of pumpkin bread and muffins (perfecting recipes for the restaurant), and he was very excited about that, so I hope he got all of those calories into his system before he puked. That was the first time I saw him actually excited for food and even begging. But this morning, he was eh about it.