About to POP?

My belly button that is. The past few days I have been having an intense pain around my belly button. It was worse at the end of the day (especially the past 2 days after long 12 hr shifts at work). It worried me a but Saturday evening on the way home from work because it was so painful, I couldn't sit still in the car on the ride home. It just feels like my skin was going to tear off and all my insides were gonna spill out (sorry for the graphic). It felt better once I got home and laid down. This repeated itself after work Sunday night. I did notice Sunday that I have my first stretch marks (really bummed about this) and they are circular around my belly button. I guess that's whats been hurting :(