Exactly 1 year ago today I was in your position. It has been the hardest thing I have ever done but now it's so worthwhile.
I really struggled in the beginning. I went Cold Turkey and I had every side effect possible (couldn't sleep, brain fog, depresssion, constant pain in my back, headaches) You name it I had it. So many times I thought of caving in a buying just one packet but the thing that kept me going is thinking about how disappointed I would feel if I smoked and I knew because it had been so hard in the beginning for me if I smoked I wouldn't bother trying to stop again. I look back and laugh now because at times I thought it was end of the world and my life was over. I couldn't imagine never having a cigarette again and felt so low. But now i'm a year on and feel great and don't worry about putting on weight. I put on 2 stone but i've managed to get 1 1/2 off so just 7lbs to go!! Eating crap was one of the things that got me through.
I smoked 20 - 30 cigarettes a day for 20 years. So if I can do it so can you. Make sure you keep to this forum because there is so much support on here for you. Good Luck to you xxxxxxxxx