Don't wish to appear rude, but has it been like this since you were born, or have you put on a bit of weight resulting on your navel sticking out more?
Can that happen then? You put on a stone or so and your belly button pops out? Jesus I hope not! Then again yeah all pregnant women have skanky belly buttons don't they.... I'm sure there is some kind of surgery. Either that or get it pierced all over and try to disguise it that way!! But wait til your 16 to get piercings and always ask your parents first!
Doolallygirl, I didn't know if malta was male or female, so I was trying to be diplmatic! Malta could well be female & pregnant. Some pregnant woman's navels do stick out, although mine didn't. Anyway malta, best to see the doc, who is the only one who can advise you professionally. P.S. I bet you a male with a red face after reading all this!
Erm yeah, men can have their belly button pierced! It looks really sexy actually. Oh and I hope a 15 year old isn't preggers. That would make me very sad indeed.
Yes, you can get it fixed. My bellybutton stuck out about 3/4 inch until I had an operation to sort it out when I was 5. Why not mention to your doctor to see if you can get it shortened on the NHS (you're under 16 so I'd imagine it'd be free).
omblod is right, it is possible you may have an umbilical hernia which can be rectified with a short 20 minute operation. See you GP who will advise you further.