I would see a pediatric GI physician about this.
Sending the stool off for culture and analysis can be done to exclude infection.
A lower endoscopy can also be considered if inflammatory bowel disease is suspected.
I would also consider blood tests to exclude celiac disease.
These options can be discussed with your personal physician.
This answer is not intended as and does not substitute for medical advice - the information presented is for patients education only. Please see your personal physician for further evaluation of your individual case.
Kevin, M.D.
www.kevinmd.com
I forgot to add he also has headaches.