I'm 25 I have hard lumps on my abdomen under my fat almost as if its like attached to the underlying muscle... And they hurt to push on. My doctor told me that these bumps on my stomach are fatty lumps caused by diet and they hurt when I push on them he said not to worry. I also went again and they did an ultrasound and saw nothing and once again said its fatty lumps and its nothing to worry about. I have also had a hernia though and so for those of you who are experiencing pain near or under your belly button I'd get that checked out to see if its a hernia. ☺ I hope this helps at least someone ...