Growing pains possibly? It's not unusual for snakes to randomly go into feed strikes, especially Balls. The more you attempt to feed, change temps, etc. the more stressed she'll get. My BP Ruby, who was my first, went 4 weeks without eating once. Why? Not a clue! She just decided not to eat.
Until she starts to show signs of distinct weight loss, I wouldn't worry. She'll eat when she's ready. Maybe she just needs some more time to get her bearings.
By the way, if you've p/k a rat and she won't take it, you can just freeze it and try again later rather than throwing it out, so long as it's been dead less than say 20 minutes. Just whack, dangle, and if she won't take it then pop it in the freezer.