Mark the level of the water, so you can tell is she has been drinking anything, but if she is active and seeming okay otherwise, I'd not worry quite yet. Our dog used to refuse to eat anything for a day when my mom went away, especially if my dad put the food in her dish (he was the big meanie who took mommie away and didn't bring her back ... a.k.a. drove her to the bus for the trip to her convention ) but after a day, if I or one of the other kids prepared her food, she's reluctantly eat it.