Chester is sick...

Hey, everyone! I normally don't ask for any help, but there is something wrong with my baby. He is refusing to eat and drink. Even if we do get him to eat something, he can't keep it down. I haven't seen him use the litter box in days, probably because he hasn't been eating or drinking anything. The only thing the vet has ruled out is that his bladder isn't blocked. They can't continue to find out what's wrong with him until they do some bloodwork, and we can't afford that right now. We probably couldn't even spare the $140 for the vet visit and anti-nausea meds... If the anti-nausea meds don't help, we will probably have to put him down. I just want to give my baby a chance; I'm not sure I would ever forgive myself if I didn't at least try to find out what was wrong with him before making that choice. The $230 I'm asking for is for bloodwork, and any help would be greatly appreciated. Thank you!