Why do i have sharp pain in my belly button?

Sharp pains: Dont know answer is too big for vague pain but if it gets worse go to er!

Lots of things: There is a long list of things that can cause abdominal pain. Unless this was just there for a few minutes and went away i would suggest getting in to see your primary care provider relatively soon. If it is there and hasn't gone away you should see a doctor right away.