Distended abdomen full of air with the abdominal pain and tenderness on left side would be suggestive of following;
1) Sub acute intestinal obstruction.
2) Meckel's diverticulitis
3) Acute mesenteric lymphadenopathy
5) Appendicitis (tenderness is on the right side though)
6) Worm colic
Apart from a stool examination and blood work for electrolytes, complete blood count and comprehensive metabolic panel, she would require an ultrasound and CT scan to ascertain the exact cause.
Please feel free for your follow up questions.
I would be happy to assist you further, if you need any more information.
Thanks for using Just Answer.
I hope that this information is helpful. If you need further information, please just send me a reply asking for clarification. Once you are satisfied, I hope you will enter a positive rating so that I will be credited for assisting you. Thanks again for using this service. Your business is appreciated.