A puppy should have 1 -2 dewormers by the time they go home at 8 weeks.
A vet doesn't have to do it. They are trying to pull something over your eyes.
I second the pumpkin. And don't worry you can't OD them on canned pumpkin. Plain Yogurt would help to settle his tummy too.
Congrats! I bet he is so cute!
Kennel him. It will make life easier for you in housebreaking and also prevent him from chewing on things and getting into trouble.