I put some money down on a puppy and the owner called and said he was going limp in the front end, he was 6 wks old. she took him to the vet and they found nothing wrong with him but i am worried there is something wrong with him. I have had this breed before with no problems but they were a lot older, Can this be a normal thing since his head weighs a lot at this time or should i stay away from getting him. she said he has been fine since so i dont know what to think