Sounds like it's time to go to the Dr, Anticrobotic.
It's a good idea to go to the Dr any time you think you broke a rib. When I broke mine, I had no idea that it had punctured my lung - I didn't notice any difficulty breathing. But I ended up getting a chest tube, put on oxygen and kept in the hospital for a few days.
(Of course, I had also broken my collarbone, another rib and shoulder blade at the same time, so I have to admit I wasn't paying a lot of attention to my breathing . . . )