Personally, I think I would take him in, but I'm paranoid having worked at a vet and knowing about all of the things that can go wrong first hand. If the vet says to take him in in the morning though, and you feel like you can make it that long, I would just keep an eye on him to make sure it doesn't get worse, and then take him.
I am very sorry to hear that your baby is sick
Keep us updated on how the pup is doing!
I am very sorry to hear that your baby is sick