How old is she? How long have you had her?

Perhaps she needs to be trained to perform a few small tasks, and then remain calm before she gets her treats? A "sit," "stay," and she doesn't get the treat is she budges before you say "okay," ... with the office Sheltie, we practiced just that way, sit, stay, waiiiiit, and I'll put the treat on the floor, still having him waiiit, then he gets to gobble it up when I say "okay!"