I have a very similar case with you. I cried whenever I pooped and thought little of it until I was eleven. One day after I turned eleven, my dad saw my tear-filled eyes after I pooped and asked what was wrong with me, I said nothing was wrong with me and he laughed, hugged me tightly and said I should cook up a more convincing lie next time. After that day, I asked some of my friends if they experienced the same thing, but they always gave me the same weird look. I'm 19 now, and glad to know that I'm not the only one with this condition.