Diana, you've only been quit SIX DAYS.
Forget about the 3 weeks using Nicorette. You were still actively feeding your addiction, even if you weren't smoking. The "first week" you refer to wasn't the first week of a quit - THIS IS.
OK, you are getting very heavy nicotine withdrawal symptoms. Please read the thread on Blood Sugar Levels - that may be a major cause of your problems. When I've finished this post, I'll try to find it for you and bring the thread to the top of the board - watch for it.
Some of your symptoms are prettay standard, but I am concerned about vomiting and diaorrhea. These could be caused by low blood sugar, and might be some general reaction to nicotine withdrawal. But they might be gastroenteritis or any number of other things. If that has been going on for more than 24 hours, go and see your doctor immediately. There may not be a problem, but you must not take chances.
Beyond that, keep remembering that you're coming to the end of Hell & Glory Week. Get thru the next couple of days, and the whole thing gets a lot easier very qwuickly. Trust me - we've all been there.
See your doc about the vomiting. Post again and tell us how you feel. Just hang in there, and don't take another puff.
image Marty
NOT A PUFF for eight months, one day, 12 hours : 4383 cigarettes not smoked saving £942.28 : 2 weeks, 1 day, 5 hours added to my life