Hi chili and welcome! Something else you might consider is getting a small sample bottle of 100% VG
juice and see if you can
vape it without a headache. PG allergies will creep up on ya and one of the first symptoms is headache and itchy eyes (in my experience). People can have sensitivities and allergies to both PG and VG and it's trial and error. Be mindful that a lot of supposedly all VG
juice is actually in reality what they call "max VG" because the flavors and nicotine have a PG base. Good luck and keep checking in. Many here can help trouble shoot these issues for you. And again ... welcome!