Kidney stone is a ten, getting stabbed in the arm is about a 7, broken tailbone at about an 8, stubbed toe at about a 5. Papercut at a 2. Single punch or slap at a 1. Getting branded was about a 3 for like 15 seconds then it dropped down to a 1.

Its all objective of course but thats pretty much my scale

Edit: depression induced phantom pain at an 6, maybe a 7. Kinda feels like what i would imagine a heart attack to feel like