Curious. I've been having a deep-seated, yet vague pain in my belly button area that radiates to the side hip, down the buttock, and back. It's often accompanied by a pressure sensation. Happens mostly with ob and prior to my period. Sometimes it goes away suddenly and I don't feel it for a few days. Is anyone else out there experiencing this? When it happens, I also get a lot of all-over the body muscle spasms.