If the one shots were in PG and you were using more PG, I guess that may cause a sore throat. If it's across the board, I might consider that possibility.
I suppose one or more ingredients in the one shots weren't agreeing with you, but if the similarity across the board was "requiring more flavoring" (although, I'm not sure I find that, personally to be true, you don't HAVE to flavor anything at any percentage, honestly, you could just try some dilution and see how it ends up). You could also start very low, since most are shake and vape, mainly.
It's possible the sweetener used (I think many one shots have sweetener as an ingredient) it is also possible that it, or at least the percentage used, is not agreeing with you somehow.
These are just guesses. IDK, but the coincidental timing seems a bit over the top, etc.
Anna