i think it could be either. i have broken 3 ribs in the past. it was a result of me standing on a boat and almost falling off. i caught myself by the windshield of the boat which slammed my body into the side of the boat (in retrospect, i'd have been better off letting my body just fall into the water).
anyway, i know that my broken ribs would literally "STOP" me from taking a deep breath, they would stop me from being able to laugh, etc without excruciating pain.
hope this is some indicator to you as to whether or not you have a broken rib.
jasmine