My puppy tested positive for parvo a few days ago and was started on IV fluids and two antibiotics. I've been feeding him rice and chicken broth but today he seems more down than before and won't even touch it. I've tried force feeding him the chicken broth with a medicine syringe but he fights back really hard. I'm really worried about him and just want him to eat something ): I know that one of the antibiotics is pretty rough on the stomach and giving it to him without food will make him even more miserable. What should I do?

He should be staying at the vet's. He may die, sorry.
Try to entice him to eat with anything he wants.