Hello, this is Kitt.
Umbilical hernias develop in and around the area of the umbilicus (belly button or navel). In addition to navel deformity and an associated bulge, the signs and symptoms include pain at or near the navel area. The hernia bulge pushes out upon the skin directly at or around the navel, distorting the normal contour and architecture, creating an 'OUTIE' instead of a normal 'INNIE' navel.
This is only an idea but I am not a professional so if you experience increased pain or problems, please see a physician sooner. The ER is always open.
Take care and keep posting.