Please advise me on bringing my 6 week old chocolate lab home tomorrow?

i will be having a puppy tomorrow, he will be 6 weeks old and i am a bit worried because a few people have said i shouldnt have him till he is 8 weeks? i have ensured my house is totally clean - iv disinfected both gardens and inside the house, and in the puppies cage. But i am really concerned he will catch something as he wont be having his first injection till the 15th December. Is is common to have a pup at 6 weeks and will he be ok? I would be really gratefull for all advise and information, thanks xx