For the first two or three days of stopping smoking, your body is effectively getting rid of the accumulated nicotine. This is the stage that is said to be difficult and accompanied by lots of unpleasant withdrawal symptoms. But what are these withdrawal symptoms exactly? All that's really happening is that your body is detoxing, flushing out not only the nicotine but all the other chemicals contained in cigarettes. At first, you may not like the way this feels very much, but you can turn this into a positive feeling - tell yourself how great it feels to be cleaning out your system and getting back on the road to full health.
After two or three days, your body will be free of nicotine and other chemicals, and will be thanking you very much indeed. As pointed out earlier, willpower tends to focus on what you are depriving yourself of. As you are now aware, you are depriving yourself of absolutely nothing other than nicotine and tar and all the other harmful things in tobacco products. The answer to "what happens next?" is simply enjoying your life and living it in a more healthy and energetic way.
For further ideas and advice and ways to stop smoking, visit the substantial resources section of this site - Stop Smoking Resources