sharp pain in belly button when i stand up?

[Brandi]

I have not been doing anything strenous, not exercising. I go to stand up and there's a sharp pain in my belly button and under my belly button. If i even sit up a certain way it feels like a pulIling pain. If i try and stretch up i immediately recoil because of the pain. It goes away and comes back. I'll get it once a month or once every couple months