I'm not entirely convinced that was the problem.
Sounds to me like something much more simple. You accidentally swallowed some of the vapor.
Nicotine being sucked into the lungs has one effect, but swallowing some has an entirely different reaction. Swallowing a single puff from an analog can easily have you in cold sweats and vomiting your guts up, but the sickness only lasts a few minutes. Sounds like that's probably what happened.
An 18mg dose would be high if you're used to 9-10mg, but it shouldn't be enough to get you that sick from a couple of puffs. Maybe give you a headache and slight nausea after a while, but nothing from a couple of puffs. With 18mg you should still be able to take half the puffs of normal without feeling any different at all.
Nah, I don't think I swallowed anything. I did a mouth hit and nose/mouth exhale. Smooth and tasty. Hit me like a freight train within 10 seconds.
The worst of it lasted a few minutes. I felt horrible for over an hour, and didn't feel right the rest of the day. Really scared the s*** outta me, to be honest.
The juice wasn't mixed. It was fully separated in the bottle and that's exactly how it was when I filled my clearo. And it tested at different nic levels in the clearo and bottle. I think that's pretty good confirmation that it wasn't mixed when the clearo was filled.
Yes, it was only 18mg/ml (+/- 2-4mg) in the clearo and no, that wouldn't have done anything to me. I've vaped everything from 6-24 without issue. My point is that I got nearly undiluted base in my clearo and that's what got me. Once shaken, sure, only 18. Before that, maybe 50.
FWIW, I got a response from the GM at the store...
"Your assumption that it was an incompletely mixed juice seems the most logical cause to me."
I'm awaiting a reply to my question of what mg/ml nic base they use.