I quit a three-pack-a-day habit in July; I can empathize with how hard it is. You aren't going to believe how good you're going to feel, though, as the weeks and months of being a non-smoker go by. You might have a little "quitter's flu" for a few weeks, but it's nothing insurmountable.
You are awesome for quitting smoking and losing weight at the same time! I decided to wait on weight loss until I was over the worst of my nicotine withdrawal, so that meant an extra fifteen pounds or so to lose...you are way smarter than I was.