You weigh 66kg and ht. is 160cm. So your BMI is more than 25. That's obese for Indian standards and short stature. So if you could also have distended abdomen, it could be because of your past alcohol or eating habits. Yes your pain could be because of Irregular colic due to post eating digestive processes or even adhesions. It could also be neurological/ autonomic bowel movements. Yes your
liver could also be one of the reasons. So go back to the gastroenterologist/hepatologist and Complete his evaluation process including CT abdomen and necessary blood tests. Once he rules out any known causes, then come back and consult a psychiatrist.