You know I fretted over this too. My family and doctor were only happy for short time with me quiting now they keep asking me when I am going to 0 and quiting vaping. I was and still proud I maded it this far for over four months. But I did work myself from 24mg to 18 then 12 but I started getting the thoughts of smoking again so now I just stopped freting and have the 18 as my all day vape and my second strings of juices are 12 so when I feel I vaped to much I just switch over to the 12 and be done with trying to buck the system in going any lower for now.
There is a time and place to listen to your doctor and family, this isn't one of them, lol. Congratulations on quitting and cut down slowly. Do what works for you.