Welcome! There are tons of info here to help you out. I'm overly thrilled that your vet is an advocate and suggested you look for a good forum to help educate you! Did he mention that the pup was too young to be away from the mother and siblings? Where ever you got the pup (I'm assuming a BYB for obvious reasons), is it possible to return it to the litter and mom until its atleast 8 weeks? Also, its illegal to sale/home pups under 8 weeks unless there is a medical reason, so if they won't keep them together until 8 weeks you should report them. Be prepared for a bumpy road. Start reading the threads on training and bite inhibition now. You will have many behavioral issues to come from this that will need to be addressed.
Good luck to you, and please stick around!
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