I personally withhold food when they are vomiting. I have had many bouts of pancreatitis with different pups over the years and the first thing the vet does is fluids, fluids, fluids....no food for the first 24 hours. Then, slowly introduce bland food. I use the Hill's ID or boiled chicken and rice.
Just make sure he is hydrated overnight and if he is still ill in the morning, I know you already know to get him to the vet. Check to be sure his gums are wet to the touch...if they are dry and sticky, he is getting dehydrated and I would get to the EC if that happens.
I hope it is just a passing little thing and he is better in the morning!
