I dont think youll ever have a problem with overfeeding your female ball. You can offer her food whenever she wants (at a young age that may be every 4-6 days) (I would consider that powerfeeding) which is something ive practiced with many of my young ball pythons. But with my experience that will not produce a larger snake. More substantial meals weekly works best. My suggestion to you is to switch her to small rats (it will be cheaper and is debatable healthier for the snake) Rather than two small meals once every 5-6 days try a rat every 7. If i am not mistaken I think it was Eugene Bessette on reptile radio that said the best way to size up a ball is feeding it mice! That can get expensive. I Fed my 11 yearold bush baby girl until age 3 Mice only lol. During the summer weeks she was pounding a dozen at one sitting! unless you breed mice that could mean 50cents to $1 a piece. So my suggestion is to go with what is available in the long run. 40 grams in mice for 1-$2 or a 50gram rat for $1-2.