We recently ordered an item but when we opened the packing we found that a vital bit was missing which prevented it working. The store kindly replaced the part with apology. Several days later we found the missing bit in the dogs favourite place. When you find out why your dog behaves like that please tell me yeanow.
They might have chipped a tooth and remembered teething from their youngster days...take it to the vet
(My apologies for saying "it", I don't know if your dog is a girl or not; believe me, I know dogs are PETS and FAMILY, not just something to shove in a purse!)