Most pediatricians disagree on the "wait one month" thing. My LC told me that it was the American Academy of Pediatrics' recommendation that breastfed babies not be given a pacifier for one month to avoid nipple confusion (she said it in a way that expressed that was the professional opinion but not necessarily one she agreed with). My pediatrician said pacifiers don't cause nipple confusion because the baby doesn't get anything of nutritive value from the pacifier, so they don't associate it with food.
I think if she needs to suck and will take a pacifier, it's probably not going to do any damage to give one to her. This is, however, a personal opinion, and the decision you make will be based on what you think is best for you and LO. If in doubt, do some more research before making a decision. :)