At 6% per flavor across the board you are way over the top so you probably overloaded your taste buds.
Here is a sample of one of my personal recipes to understand how to approach it. Basically I'm looking for a specific sour sweet in this one since I loath blueberry. To get there it seems as though only two things are needed. But as you will often find it can take much more than what you might think you need. There are a hundred shades of black and white which are all considered gray.
I know most of my recipes are good with a bit of Ethyl Maltol to round them off. I also know which of my fruits won't be over the top sweet. Something you might not think about is the fact vinegar (all types will work different) can enhance sour or pronounce certain flavors more than others. I have sometimes also used Blue Agave to sweeten, other times marshmallow, but I also use the TFA sweet, TFA cotton or the TFA circus cotton candy and sometimes a combo of sweetners including menthol. But all of this flavoring combined should be around 10-15% or less (using ejuice Me Up calculator) and the flavor is plentiful.
30ml Blueberry Lemon
4.0% / 20 drop blueberry extra
3.4% / 24 drop lemon
1.3% / 8 drop green apple
2.0% / 12 drop sweetener
2.0% / 12 drop koolada
1.3% / 8 drop ethyl maltol
0.6% / 4 drop cider vinegar
1.0% / 6 drop marshmallow
