It very well could be a PG allergy, go to 100% vg and see if it clears up.. Heathers Heavenly Vape carrys some unflavored e juice in a 100% vg, try that, see if it clears up..
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I'm suggesting you go to unflavored because some flavorings have a PG base.. if this unflavored works for you and it clears up, then you can begin purchasing flavored juices from a purity line that are actually 100 % VG.
As a beside, I would quit vaping in the meantime until you can get the vg juice.