Weird bumps on puppy

Question
I just purchased a great dane puppy about 3 days ago and have noticed one issue with him. His head and legs have quite a few bumps on them.

He has a soft and fluffy coat, but the bumps can be felt when petting him. He has quite a few from his nose region to the top of his head.

Some are little scabs and other bumps have a yellow, flaky look to them ( more like a sunburn peel).

I bathed him in a medicated oatmeal treatment and he is scratching far less, but I do not know what it could be. He was being fed pedigree and I have switched him to a merrick brand food.

Someone said food allergy, but I am curious as to what it really could be. His vet appointment isnt for another week and since he is being enrolled in a plan, they wont see him or let me enroll him until 9 weeks of age and if I come in now it will be a "emergency visit"

Mama dane had fleas ( since she was a outside dog) and so he had a few on him that I could see in his light fur but after his treatment I have not seen any at all on him.

Answer
Usually in young puppies with bumps and crusts, that is a Staph bacterial skin infection.  These pustules rupture and cause the skin to flake and peel as you described.  You can bathe the pup in an antibacterial shampoo, like 4% chlorhexidine that your vet should have.  Some pups require antibiotics, but I like to let them fight the infection off themselves if possible to help build up immunity against Staph.  Sometimes there is a food allergy, but sometimes there are skin parasites or just a dirty environment that leads to the infections.