Hi. Well VItamin D isnt actaully related to these symtpoms. It helps with bone growth so I think you should find another cause of her problems. At this age when child steps into puberty abdominal pain
is common and you shouldnt worry about it. If it persists then some more serious diagnosis need to be considered. Such as food allergies, crohn disease or ulcerative colitis
Usualy labs tests wont show anything abnormal, some of the imaging techniques should be done. If pain becomes permanent I suggest to do colonoscopy
and abdominal ultrasound
. Wish you good health.