Don't worry, he'll be fine.
The vet told me that my Button had to rest, no jumping about etc till the stitches came out. He should have told Button!
I managed to keep him fairly still for a day, by confining him to a crate where he howled the place down, then he was up & raring to go. I have 4 other dogs he was chasing around like a complete idiot, back to his usual self
He came to no harm at all.
The "Recovery Pack" the vets charged me £10 for was a complete waste of money....he turned his nose up at the food & was having nothing to do with the collar! He was doing himself more harm trying to get himself out of it!