It depends on the snake, I have seen instances where they have gone off feed for over a year. It's stressful when they don't eat, but they can generally go a long time without food, unless they start losing weight. How long have you had her? I say if your husbandry is correct, try not to stress about it. I buy my f/t rats from shows in my area, and I also found a local rat breeder nearby from craigslist so if I run out before the next show I just go to him. Good luck.