Nope. Assuming she's comfortable and secure in her environment with you, a stable diet of appropriately sized rats will be good for her entire life.
Be sure to keep asking questions if you have trouble getting her eating with you. Every now again the bigger ones can be finicky after going to a new home and there are things you can try to help her out. The best thing may be to let her adjust for a bit on her own until she is eating regularly. Yes, this means trying to avoid taking her out and moving her around unnecessarily (which I know can be tough with your "shiny new toy"). It may not make a difference at all, or, it may make all the difference in the world. They each have their own personalities when it comes to feeding.
Enjoy your new addition!