[ally173]

i am sorry to hear about your baby; this is exactly what happened to my dog; she had 6 episodes of vomiting blood and ended up in the ER every time because i couldn't stop it. she will stop eating and just vomit all day. so finally this year the vet did an endoscopy with biopsy to diagnose her and it was IBD (inflammatory bowel disease). her case was severe chronic IBD; this is a very serious disease that can't be cured but controlled with meds and diet.
he put her on prednisone to bring down the inflammation and she couldn't tolerate any dog food ; prescription food or high quality food; i tried everything.
her GI tract needed to heal so the only thing that worked for her was a bland diet; of ground turkey and oatmeal.
by the way IBD dogs are sensitive to chicken, beef, rice and sometimes lamb.
so you have to try a different protein; mine can eat turkey.
so for now since ur dog keeps vomiting that means he's not tolerating the food. and since he had 3 episodes that means the inflammation is bad; it needs to be controlled.
please talk to ur vet about IBD and see if he can give you anything.
but for now you need to feed a bland homecooked diet and don't forget to add the probiotic. by the way antibiotic makes things worst because they kill the good bacteria too. speak to you vet. good luck