Pain in abdomen. My pain in d abdomen?.

I have been suffering from a pain in d right side of abdomen near the liver area from 6 months. The pain increases after i eat and i could not sit for more time because that part becomes numb n i feel like it is getting twisted up inside. I undergone Endoscopy, 2d echo, ultrasound for abdomen but all are negative and my doctor advised me to go for CT SCAN abdomen. What is the reason for this...also i took nexito plus tablets for 2 months because of anxiety and depression and i stopped them abruptly last week. But from 3 days i have been experiencing increased anxiety, pain in d chest and hissing sound in my ears. Are these withdrawl symptoms of nexito plus? N what is d reason for my pain in d abdomen?.. Also note that i used to smoke and drink regularly but i stopped them 7 months back abruptly.