These pains in your child in the belly could be related to Lactose or Milk intolerance, which is quite common in Indian children, so please do not give her milk at night. I also hope she is not constipated or passing hardstools with difficulty. A third possibility is Meckels Diverticulitis related to acid production in excess. I sense the only way forward for you is to see a good Pediatrician who completes a diagnostic workup after a thorough history and investigations.