2 suggestions:
1. Capsaicin cream (
http://www.experienceproject.com/sto...y-Kind/1979813 ). Personally i never tried, but i read a few articles and it sounds intense. Read an article or 2 and pay attention to the precautions as ti sounds like if used in the wrong way, could cause more damage than expected.
2. If you have access to ice, try numbing your cheeks before spanking. collect 2 different spanking instruments: wooden spoon and hair brush. Get a larger trash bag and place a good amount of ice in it (enough to cover your entire bottom). Sit with your cheeks directly in contact with the ice until you are numb (3-4 minutes); spank right cheek with the wooden spoon 75 times; then the left cheek. As soon as you are done spanking, sit back on the ice for another 3-4 minutes. Spank cheeks again another 75 times (1st right, than left) with flat side of hair brush. Back on ice for another 3-4 minutes, followed by another 75 spanks to each cheek with bristle side of hair brush.
I doubt you will be able to make yourself cry as human instinct will probably prevent you from hitting yourself hard enough. However, the numbing of your cheeks from the ice will allow you to hit harder than normal, so your are likely to feel more after.... Let me know how they work out if you try them. Good luck and enjoy