And as far as what beemommy said, I semi agree, but you can give it to her if she's in pain and cranky and needs relief. Plus By the time you figure out if she's going to be fussy over it or not, the vaccines should have started to set in already, I wouldn't give it too her unless she just becomes real cranky at home.
Best thing is right after they're done, pick her up, hold her close, and comfort her to the best of your abilities, other then that, the best thing is Tylenol at this point, just like @ilovemyfam had said, because of the injection sensitivity, and it can sometimes cause a low grade fever.