Loving you and your quit Rooter. Congratulations on the THREE WEEKS. That's a major accomplishment. Regarding the craves, your brain is still rewiring itself. It takes time. A lot of it is anxiety, frustration, even anger and these are a normal part of the human experience. We have conditioned our brain to interpret them as cravings for nicotine. They're really not. That little bit was an epiphany for me; if nicotine is not part of the problem (after 72 hours is out of the system), it cannot logically be part of the solution.
BubbaM in June chronicled that the 'crave' is the mind functioning from the brain stem in a primitive fight or flight mode. To move to the temporal lobes and out of the crave, one needs to visual or auditory cues, i.e. pictures of loved ones, or relaxing music (the metal and heavy percussion that most folks listen to in the gym shift you INTO the brain stem, something like Mozart or Beethoven shift you out).
Very pleased you've made it three weeks man. Really. Proud to be quit with you today.