A warm bath helps a little i never had that pain with my son just my daughter.

Yes I just thought it was because its pierced or because I had a surgery and they went in at my belly button

Yes mine even looks bruised, there's like a dark circle around it.

I did with my daughter it always felt bruised, my belly button never popped though. It's just the skin stretching, it would hurt so bad sometimes that I'd cry.