Adding more fruit and fiber to your diet should help. Really force the fluids because they not only benefit your bowels, your system needs them to flush out the nicotine. So far today time has gone faster which to me is a good sign. The car is no problem for me. I never smoke in the house or car.
Some folks find benefit to their bowel regularity through walking.
You're right mary, the computer is a killer for many people. It's just so easy to add a cigarette when we're sitting and quietly working away. Getting up is probably your best option, however add other tension relievers. Such as just closing your eyes and leaning back for a few moments, take deep breaths and feel your body relax, imagine cool water flowing down across your face and over your body to the floor. I even forgot my coffee that morning.