it felt like somethng popped out between my ribs
Something a bit like this??
Neither of these problems sound that much like cramp..
Steph's sounds a bit like costrochondral dislocation, where the front tip of the rib subluxes or dislocates out from the cartilage
Nib's could be cramp, but if you're getting an obvious physical lump it makes you wonder if you might have a hernia - classic hernias are in the groin but you can get hernias where you describe - paraumbilical or spigelian hernias - henceforth to be known as the "beastmaker hernia" - the doctor prescribes a few less flashy frontlevers on the BM!