I smoked for 24 yrs then cold turkey "BAM", if someone else can do it, you can do it. One of the hardest things I've ever done, about 1 1/2 months of pure misery for my coworkers
and a lot of lung clearing. To each his own on substituting one nicotine for another, the sooner you get it out of your system the better, I chose not to prolong the addiction and acquire the cost with patches,gums etc,it's nicotine.
Oh and I know it's a lot to ask but caffeine doesn't help at all, "both at the same time? you say" talk about a rush, hold off on the caffeine till you get the nicotine out, you and your system won't have to deal with the nicotine as hard. Don't worry about the weight as long as you don't go or get overweight, you'll feel and smell so much better and the sense of accomplishment is well worth anything more than what you'll have to endure in the process. If your going to snack to stay busy, carrot sticks,celery, your finger nails,whatever.
Do not grab for the things
you know are fattening. If some of us would only treat ourselves as well as our bikes
Bless You
, Good Luck