She probably was still hungry... Every dog has a different metabolism. My kiddos are on raw and Zeus gets 1.5 oz more than the suggested amount because his metabolism is fast. He gets almost the same as my 11lb cat and Zeus is only 6lb.
Did you try raising the amount? If so, did she gain weight? If you and she both liked raw and did not slowly raise the amount, I would recommend trying that.
But, if she's enjoying Orijen, I would just stick with it instead of going back and forth with different foods.