I've smoked for years now and these problems have just started to occur. On four separate occasions I've found myself getting extremely nauseous and light headed after smoking. I also have severe lower stomach pain when this happens. On the worst of these occasions my joints began to lock up and I could barely walk. I slipped in and out of consciousness and even found myself sitting on the ground after blacking out. My friends were eventually able to help me inside. After throwing up a small amount I was able to get in bed and sleep it off. I still had a headache the next day but the other symptoms were gone. It doesn't always happen. It seems that the more I smoke in a sitting the more likely I am to show these symptoms. I have already decided to cut back drastically and work towards quitting but I want to make sure something worse isn't happening.