Re: Odd belly button feeling...what is it?
Is sounds like your abdominal muscles are separating. I had this with my first PG (I had a 4 pack and really flat tummy before) and it was really painful by 20-24 weeks, then it got better. The doc said it's common for the two sets of muscles to begin to pull apart as your uterus grows and stretches everything out. It always starts in that place, right behind the belly button.
By my last PG, it hadn't gone back to normal (my PG's were only 1 year apart) and it didn't hurt. But by the end I could actually see her stick baby parts through the hole. You could almost see the shape of a tiny little foot, and it felt SOOOO weird because there was only skin and uterus between her foot and the world, and no ab muscle.
DS born 07/05/2003
DD born 3/24/2005