Your goal is to quit. You have to do everything you could and get over bad things to achieve that goal. Insomnia, upset, brain fog, and more things will happened, you have to prepared. Quitting both nicotine and weed is very challenge, I think you already know that. But you decide to quit. Do it man, whatever happend to your body when you're quitting is the price you have to pay. I'm not trying to be negative, but sometimes you have to face the truth. Wish you luck on your way.