Glad he is better today.
When Coco has the squits I don't worry too much unless she is totally out of sorts or it goes on for more than about 24 hours. It is usually because she has snaffled something disgusting that she shouldn't have or someone has given her the wrong sort of treats
If it lasts longer, or the dog is very subdued and poorly, they I would talk to the vet as it could be something like a bug or bacterial infection rather than just something that they need to get out of their system. Obviously, with a very young pup or generally weak or poorly dog, a vet call would be wise earlier on.
You can withhold food or feed a little boiled chicken or fish with some rice. Tinned, plain pumpkin is very good for settling a runny tummy too and I often add some live yogurt. As long as they are lively and drinking enough, I don't think withholding food for a day does any harm.