My yorkie puppy was doing this when I first brought her home, too. The vet told me that she was just getting used to the air conditioner in my house and not to worry too much about it. Also, if you take her outside in the heat and then bring her back into the air conditioner, it is probably making her sneeze. AND she is probably really close to the ground, so the grass may be making her sneeze, too. Unless she stops eating or starts to not act like herself, I would not worry too much about it. She is probably just adjusting to her new home!
