Hello my name is Billie. Puppies start to adjust to you almost instantly! You just need to be careful with introducing to bigger dogs and also be careful of other dogs not vaccinated (as others have said). Have the puppy sleep with a shirt or sweater of yours that smells like you to allow the puppy to adjust and feel more comfortable in it's new home. It's almost like having a newborn where you need to keep an eye on the puppy and give it special treatment by the age of 10-12 weeks the puppy should start to become fully aware of his surroundings! Good luck with the pup!