I agree with this suggestion. If you want to try 100% without a huge investment, get a couple of bottles at MBV. Get a tobacco flavor (since you said that's all you vape) and get a bottle of unflavored. Try them out for a couple of days and see how it works. If you still feel sick, try vaping only the unflavored. If the unflavored doesn't make you feel bad, it could be you are allergic to some flavorings.
Do you have any food/nut allergies? Some flavorings can be extracted from the real thing it's supposed to taste like, which could cause a reaction. And I bet the reaction would be different with vaping since it's inhaled and not ingested.
Definitely try the 100% VG route. If that doesn't work, we can cross another bridge.
Im not VG/PG sensitive, but there are some VG liquids I do enjoy.
Also, I vape 24mg because otherwise I don't get enough throat hit and I want to smoke cigs
Also: You should ALWAYS drink plenty of water when vaping. Even if you don't feel dehydrated, you still could be. And a hangover is essentially dehydration. Ever wake up one morning after a night of hard drinking with your head hurting and a general nasty gross feeling? That's just dehydration from your body trying to metabolize and get rid of all the alcohol/junk.
One last thing: There are withdrawal symptoms from quitting smoking that are different than just having that "withdrawal" feeling of needing a cigarette. I experienced symptoms for about a month after I quit. I had a bit of trouble sleeping, I would wake up feeling tired, I had random muscle aches, sore throat, it was gross. That stuff can be normal for some people after giving up tobacco.
I hope you find a solution to your problem!
, but I will give it anyway 
