HI. Your Problem is Pain in abdomen and gas formation. due to this i feel tried,serve headache & sleep issue for a long time.. If the USG and CT are normal, we can think this as a problem of irritable bowel syndrome/ infection of the intestines. A proper course of antibiotic must have been given to you by this time. It looks you need to look into your dietary habits- there must be something in food that is not suitable for your intestines, identify and stop completely. Secondly you may have to change your lifestyle- the anxiety is one of the most important factors in problems like you have. Thirdly add probiotics avai;able as Pre-pro / Darolac, Activated charcoal tablets like gasex, avoid late nights, you should get the complete and sound sleep, No stress/ worries/ anxiety- change the situation around you... All this will help you to have a proper betterment. At Maximum you can undergo colonoscopy to rule out any organic problem