My friend and I were just grappling a little. BTW, grappling's not exactly my forte and my elasticity is questionable. He took me down and tried to pass my guard; his knee landed on my sternum, and i heard a crack. It wasn't really a terrible, just more of a "i popped my knuckle" kind of crack. I woke up the next day and felt a sharp pain in my sternum. It's been about 5 days and the pain has seemingly gone down a little, but it's changed. Now, this area underneath my chest muscles hurt. If I try to stretch my pecs, it hurts; also, when i cough it hurts a LOT more. I'm not here to whine about the pain. Frankly, it's not THAT bad. It's just making me afraid to workout at the gym, and i'm a bit hesitant to see a doctor, cause i don't have any health insurance.