A dream came true with lots of whipping and a question

After long time of dreaming, I finally arranged a session with a local professional Mistress/Domme, to be used as a basement slave.

I was pegged hard and made to suck and choke on the strapon, but the best part for me, was the whipping! She used a bullwhip(if thats what you call it), whipping my back and my ass. While I was screaming gagged from the pain, a small burn on my skin would pass by. She would whip me 3-4 times, and then stop. Just in the right time.

Question: In scale of pain, I asked her to go at 8. But I can't remember how we call it! Is it scale? grade? where base on the number you say, she applies her hits.