Re: Getting annoying
From what I can tell, not feeling well after smoking shisha comes from aggressive smoking. When you smoke a Western style pipe constantly drawing on it or not having it properly tamped can result in the dreaded tongue bite. Narghiles are the same in that if you aggressively smoke without pausing between draws chances are you'll take in too much too quickly and regret it. Smoking should be a relaxing, social endeavor which pleases the senses. Over indulging in tobacco is as bad an idea as over indulging in alcohol.
It seems that the best time to smoke is during or after a meal as someone pointed out. Also, avoid crappy coals like Rolland and stick with natural coals if possible and high quality instant lights other wise. Also, never start to smoke until the coals have started to ash and the surface is no longer black.