I had a kidney stone once. Let me describe it for you (don't read if you don't like pain): [spoiler]I let out a loud groan as I felt pain in my side. I felt I had to go to the bathroom but saw an odd color is the water when I was done. I went to the hospital in immense pain, I had heard it feels like childbirth. I always felt I had to pee, even though when I tried to I could not. Throughout my time at the hospital i did slowly begin to feel better. In the end they said there is evidence that I could have had a kidney stone, but none that I still had it, so I went home. From time to time I have a similar feeling and thing "oh no, please NO!" Luckily I don't believe that after that I have gotten another one.[/spoiler]