Every so often I have these anal or rectal spasms. They are very painful, but fortunately do no last long. I always seem to get them when my intestines have been particularly irritable. Anyway, on Wikipedia they are called "Proctalgia fugax (or levator syndrome, also known as anal cold) is a severe, episodic, rectal and sacrococcygeal pain.[1] It can be caused by cramp of the pubococcygeus or levator ani muscles. It most often occurs in the middle of the night[3] and lasts from seconds to minutes..." Anyone else have these too?