Nerves grow back, oh yes they do. The tiny ones in your respiratory tract. Your smeller and taster will work better, and my hearing actually got better (I have eustachian tubes the size of Michael Jackson's   nose, and irritation shuts 'em down and makes my hearing suck as bad as...something that sucks a lot.)

With the perky new nerves comes an increase in feeling that may not be all that welcome to start out with. Respiratory irritation: it's not that it wasn't there before. You just didn't feel it. You might go through a phase where your throat's sore or you have a tickly cough that will drive you nuts for a bit. It will pass. Take it as a sign that you're healing.

The loogie-launching mentioned by s&r above - same thing. Think about what the stuff does to you when it doesn't go anywhere. Drink a lot of water - it will help.

Now, expect, in a month or two, to have THAT dream. (has anyone who's quit not had it?) You'll be in your little dream world, and you'll be talking to the usual dreamland buddies. The guy with three heads offers to buy you a drink, so you whip out your wings and fly up to the bar, because you're bored with going up the slide. You sit there with the three-headed guy, Bugs Bunny and Jack Keruac, discussing favorite ice cream flavors, and then, the most frightening thing happens. It makes your stomach seize and your blood drain to your feet in the icy grip of terror. You lift your hand to your mouth and inhale the cigarette that's been there the whole time, and realize, "HOLY MOTHER OF PEARL, I AM SMOKING!!! HOW DID THIS HAPPEN? I DO NOT SMOKE...I STOPPED THAT SHIT!!! OH WHAT HAVE I DONE!!!???" Then you wake up in a cold sweat and realize it was just a dream.

Of course, it's not always the same dream. Sometimes it's Daffy Duck instead of Bugs.