Welcome. I have no idea if you're sick, or if it's a reaction to quitting.
One thing you need to realize is - you've never quit before. People QUIT one time, everything else is a stoppage.
Also, we don't "give it a shot" here. We quit, and we quit hard. No room for excuses. No tolerance for caving. When you talk about giving it a shot, you are keeping a door open for nicotine to sneak back into your life.
If you jump in with both feet, drink the Kool-Aid, and listen to the vets, there is a 100% chance that you will stay quit for the rest of your life, one day at a time.
Find the December Quit Group. Post roll. Get to know the guys in your group. Collect digits. Mine are a PM away. Give your digits out.
Right now we are a group of internet strangers. Soon many of us will be your brothers - all with one thing in common - we are nicotine addicts. We know how addicts think and talk, and we help people quit, because we were all once exactly where you are.
BTW, I was an active user for longer than you've been alive (24 yrs.). Kudos for deciding to quit at such a young age.