It appears you ran your hand through in a flat position, with fingers perpendicular to the wheels. . If you look at the diagram on the machine, you should hold your hand vertically and run your fingers parallel through the wheels to more effectively crush your hand.
Seriously, the other day on the bus I was enjoying my favorite snack, skunk glands infused with fox urine, and people had the audacity to tell me I can’t put these things in my own body. Dictators.