My initial problem when I started vaping was not enough TH. It took me a while to figure out vaping is a longer lighter drag than with analogs. It really is trial and error with juice, batteries, styles (I started with 510 then got 808). I also read that when you smoke, it kills your cilia - the small hairs that filter the air you breathe. When you vape that first week before they have regenerated, you cough a lot (didn't happen to me, but read that it does and it happens to my friend). The other thing, if you notice when you exhale vapor solely through your nose, it feels odd and wet - water vapor. It can loosen some of that junk in your lungs. I'm sure I'm failing miserably at trying to explain this . Perhaps if you search previous posts, you will be able to find the post I'm referring to, bc that person explained it so well.
I'm still fairly new at vaping. It took me a while to stop the analogs. I finally quit the analogs on March 10, but before that, I used analogs along with vaping for over a month. Hang in there and you may have to do some trial and error.