I just got a shar pei puppy today and he wont play or eat but is healthy?

He is 13 weeks. He wont let me pet him or pick him up like his owners were. When at his previous home i fed him treats and he was fine. I have been calm and gentile and move slow but it doesnt seem to help. She investigates and sorta follows me around and let my girlfriend pet him but when its time to pick him up or go out side he hides in the corner and i have to pick him up and he screams but then lets me hold him and is fine. He has not eaten or drank since i got him today so i left food and water in his crate for him and let her have some quiet alone time. She does not seem to miss her old home and is very healthy. What should I do??????