For the last few days I've had heavy chest pain and have been unable to sleep. I've had trouble breathing and my chest feels like somebody is standing on it. This started when I had around 100 pounds of weight held onto my chest for around ten seconds. Now I believe the muscle has swelled up and is causing me the discomfort, however, is it possible that the sternum could have been actually pushed back into me? I don't know if I'm just being paranoid, but but when I run my hand across my chest it actually feels farther in. I'm hoping it's just bruised muscle..