I started vaping about 3 weeks ago and all was good til a couple of days ago. I am using the Ego Twist and even after changing the cartomizer in the tank I am getting hardly and vapor and when I heat the atomizer up a bit to get vapor I end up with a burnt taste I have tried 3 different tanks all the same even tried just the cartomizer on its own without being in a tank same bloody thing? Have my juices gone bad?! They're only 3 weeks old.