I would say yah, give her another mouse. Get a scale from wal-mart if you dont have one perhaps, it will help you get a better feeling of how much to feed your snake by comparing weight of prey to the weight of the snake. You can definitely up her to small rats or rat pups at this point. Meals should be approx the same size of the thickest part of the snake and about 10-15% of the body weight.