From what I've learned and am experiencing now, balls will go on hungry strikes. I'm used to keeping and breeding retics, so food was never refused lol. I wouldn't worry at all. Try and offer food in another 6 days or so and see what happens. Also watch her weight to make sure she's not losing that much. Quick questions though.....What are your temps like in her enclosure, have you recently moved her to a new cage, and does she have a hide. I've noticed that unlike retics, balls stress a little more easily and have a real need to feel secure.