If he is vomiting non stop and also has diarrhea and you can't get him hydrated then you should seriously consider the emergency vet.
If his pancreas levels were sky high did the vet tell you to fast him too or did they think the time there was enough?
You can read about pancreatitis here
http://www.marvistavet.com/html/body_canine_pancreatitis.html
You might ask the emergency vet if they can show you how to do subcutaneous fluids through the weekend yourself. Some vets will and some won't.
If you can get the Reglan and Flagyl in him and he can hold it down that might help.
If you can add some plain pedialyte to his water or make him pedialyte ice cubes to lick this might help with hydration.
You are the only one who can see how much he is vomiting. Check his mouth to see if it seems dry and the gums tacky. Pull the skin up over his shoulders and see if it sticks there or falls back down - those are two checks for dehydration.
Sometimes illness like this is due to a non food item stuck along the intestinal tract which could trigger the backwash into the pancreas of the duodenal fluids. You can ask the emergency vet if a towel or tennis ball etc could cause this. If your dog chews on things like that its a thought to consider.
If you feel your dog is getting worse not better then I'd consider the trip to the emergency vet.
Hope this helps you!
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