Whenever you introduce some significant change in your life, you will find it reflected in your dreams. Dreaming is the by-product of altering physiological changes. When you stop smoking cigarettes and begin vaping, you are initiating a huge change in your daily habits. This requires some reorganizing of your thought processes. Vaping might seem a decent substitute for smoking, but your brain and body know there's a change. Dreaming amps up in response to this kind of change and (if you recall) you will do a lot of processing to catch up with the altered behaviors and chemistry that you previously experienced. Dreaming is the result of the brain working to organize and process any novel experience and integrate it into your normal routine. The more change that is introduced to your daily life, the more vivid dreams you'll experience. They will settle down after a time. Your brain uses sleep as housekeeping time--organize, categorize and file away anything relevant and useful to your daily life (and toss out the irrelevant). It can be very enjoyable if you can sit back and enjoy the ride. Write them down very soon after waking (while still in bed and emerging from the sleep state). They can be very entertaining and revealing.