Hi, welcome to our site. I am Dr Saumya Mittal, MD. Read your query. That is a very significant question and i appreciate your problem. I will try my best to answer your query I think you need to understand that the nerves of many parts of the body are related. When doing colonoscopy or endoscopy, air is infused in the system so that we can visualize this system. When this air is left back, and some part of it is almost there till it gets reabsorbed, there may be pain in the stomach and often in back. The pain you may have had initially is due to local action. The nerves of stomach/intestine are affected. Then the other related nerves are affected and this may lead to backache. It is caller referred pain. Referred pain is like when two parts of the body are supplied by the same nerve, the brain may mistakenly read that the pain is in one part of the body while it is actually in another part of the body. You may therefore just wait for the pain to pass. If it does not pass meet the doctor to rule out the possibility of injury I hope this helps you. Inform the reports mentioned above/if any other so I can be of help further. I have given you the answer to the maximum considering the information provided. The results of the tests could further enhance my answer to you. Please do understand that some details could be extracted from a detailed history and examination. Please feel free to ask another query. I would be glad to help you. Looking forward to your return query with the details asked so that I can help you further. (If the answer has helped you, please indicate this) Best of luck. Dr Mittal. MBBS, MD (Internal Medicine), CC (Diabetes Mellitus), DNB (Neurology) Consultant Physician and Diabetologist JS Hospital Ex Apollo Hospital, Delhi Ex Kailash Hospital, Noida