I am trying to stop smoking because of my COPD.I have been using an e-cig to do this.The only problem I have with this it sometimes seems to affect my chest at times so I stop using the e-cig for a day .It is a strange feeling I get in my chest,not a pain but just this feeling which I can't describe.The best way I can describe it is a tight feeling which makes me a bit breathless.Any advice would be very welcome.