Please help my dog, Petey. He is very sick and will have some serious vet bills, and I have absolutely nothing

I am currently at the vet ER. I don't have a diagnosis or a cost of treatment yet, but will update this as I learn more. He is up to date on his shots, but they are running a parvo test first. This vet trip is $250 already, and I don't even know what's wrong with him yet.

As some of you may know, I was recently in the hospital for over a week with an extremely traumatic injury. While I was in the hospital, I had to put Petey up with a foster. He fell in love with her, and she did nothing wrong. Unfortunately, over the last few days, Petey hasn't been himself. He won't eat anything or drink anything. I got him the medicine the foster said he needed and decided it was time to go pick the little fella up, as I am on the mend and no longer bedridden.

When I picked him up this morning, it seemed as though he was through the worst of it and actually seemed to be shaking back quite well. As soon as I got him home, though, he resumed his lethargy and wouldn't eat anything again. He is choking and vomiting up foamy white stuff, and his nose has gone from runny and mucusy to dry and crusty. I truly felt like he was going to die in my arms. I rescued him from a tough living situation and have done the best I can so far. But I am broke. Broke broke. And I could not live with myself if I was forced to surrender him to the vet. I love him too much, and he loves me. He needs me.

Please, if you can help at all, do so. For Petey, not for me. If you are unable or unwilling to donate, please, please share this post with as many people as you can so I can get my little guy the help he needs.

Thank you for taking the time to read this. If nothing else, please pray for my pup.