You may want to try a manual battery if you are not already. I have seen noticed some problems with suck activated batteries causing mild symptoms of pleurisy and/or accessory respiratory muscle fatigue especially if you are vaping often. A good e-cig that requires very little effort may alleviate the lung and chest discomfort. The manual batts require essentially no effort and you may find yourself making fewer "false" inhalation attempts. With that said, sounds like you are off the analogs. That's what is important. Congrats!