Proctalgia Fugax (at night pain in the rectal area).
This was the miracle cure for me and I know it sounds crazy but: Lie down and get in a position of a woman giving birth. Use a TENs device and place the electrode on the inside crease on the lower buttocks, about where the crease ends. Use 1 electrode on each side. Also make sure the area is dry. As soon as you realize you are having an episode set this up as quickly as you can. The relief will be almost instant and complete if you have the electrodes placed properly. I have suffered all my life with this, with episodes happening usually at night ~ once a month or so. This method has never failed me to relieve the pain. I am a male so I have to keep that area hair free because the electrodes are adhesive gel. I've tried everything before this, sitting on a tennis ball, sitting on the edge of the bath tub etc. and nothing else worked. The TENS unit I got on amazon.com, made by santa medical, about $30. and I use it also for sore back, shoulders, muscles. It feels like a vibration and is very soothing. Of course I cannot guarantee this will work for anybody but it is a life saver for me.