Hello, and thank you everyone for your awesome answers. Too much for me to quote all.
Thank you for the links. I'll be sure to read them later. So sleep problems are to be expected during the transition then? As of lately, after
vaping, I'm a light sleeper. Sounds as discrete as a (normal) car passing by is enough to wake me up. It didn't bother me before
vaping (still on analog)
I'm using Kanger subtank 7ml, but changed the pre-installed 0.5 ohms coil to the included 1.2 ohms. Using kbox, set to 20W. Not a cloud chaser, I'm smoking/
vaping to satisfy the nic addiction

So 15ml/day is a bit too much? What 'dose' would you say is normal? I want to set it as the next cut down goal.
I'll see if I can get my hands on some higher nic juices to try out. I got a few friends vaping, and they might have higher ones.
'The purge' theory is interesting. So this symptoms might be from my body doing house cleaning? I do notice 1 more symptoms, but forgot to write it. My urine got a little smelly, like chemical stuff kind of smell. It was also smelly when I did too much analogs in the past, but that was kinda burnt smell (hard to describe). So this is a good thing then? I was afraid that the symptoms are a bad thing, and instead of getting better, it will get worse in the future...
Again thank you all for your great answers