I haven’t delved that deep into its chemistry, but it’s great that you were able to figure it out like this.
Are these aromas or short/longfills, by the way? That might matter too. Who knows what they mix into a shortfill to make it tastier.
edit.: sorry, I read through the topic, I got the answer. I also recommend homemade liquids. Zsolt’s flavorless “technique” can also rule out a lot, e.g. if it works, and your problem doesn’t reappear, then it’s almost certain that there was something in those liquids that your body didn’t like.
The taste isn’t great, but it’s not terrible either, it’s livable, and in my opinion, a much better alternative than an analog cigarette.
Maybe you could mention where you are, there’s a big crowd, maybe someone can help you with something 
Oh, and yes, one more piece of advice, get acquainted with the world of RTAs. For the price of one atomizer, you get half a year’s supply of wire and cotton. But it’s not necessarily about the price, but rather so you don’t have the problem of “where do I suddenly get an atomizer because I need one”.