Help! my dog is projectile vomiting?

I am not a vet and I am not sure if this will help much, but I would try to give it pedialyte. This will keep the dog hydrated from all the water she is losing. I have given it to even tiny animals with no trouble (I found a baby flying squirrell and gave it this). Maybe ask the vet if that would be OK. I think it would be, but again, I am not a vet...