I would wait a full week without handling before you feed her. I would also invest in a kitchen scale so you can get her weight. That will help us decide what you should feed her. Assuming she's a full grown adult, I would offer her a weaned rat if she very, very skinny (a picture of her would help). If she's not too thin, I would feed her a small rat. Again, it's best to know her weight and have a picture of her so we aren't guessing on what to feed her.