i recently was using my crutches and one slipped from underneath from me. i didnt fall but my head went back with some force and i felt a terrible tear  in my chest, which i got terrible pain from, i have sstill got this pain that radiates from mt sternam over my right breast and into my top of my back and spine and shoulder. could anybody tell me what muscle this could be, as pain is terrible.

thanks

 

sp