Carbonating DERP!

I may have answered my questions while typing it out, but some verification might help.

I dialed my regulator to 12 psi to carb a beer in my kegerator at 40 degF. I did all of this at room temp. Once I placed the CO2 and the keg in the kegerator, the psi dropped to 8. I understand there will be a drop, but do I need to dial-up the ppm in the kegerator to 12psi or is it already giving my beer 12 psi but falsely reading it low? I assume the former, but I wanted to make sure.

THANKS DOOOOOOOOODZ

"psi"

ppm is a whole 'nuther thing

And it's pretty typical for a regulator to take some time to equalize to a big temperature change - like, moving it from the room into a kegerator.
Just adjust the pressure ("psi") and let it sit for 24 hours, check again and tweak it, and it should settle down...

Cheers!

Ha, OP edited. Sorry, been studying esters/phenols all day.