There are many different causes of chest pain, particularly because there are many different organs within the region that can cause pain. These include your ribs, your intercostal muscles, and the skin around your chest, your back (including the spine, nerves and back muscles), your lung and its lining (pleura), or even the trachea, your heart (including the sac it sits in), the aorta (a large blood vessel), your esophagus and digestive tract, your diaphragm and lastly, your stomach, gallbladder and pancreas.
If you have had any falls or sustained any injuries the sharp pain may be due to a structural injury to your ribs (potentially fractured). As chest pain can be associated with dangerous conditions, I suggest you see your doctor - particularly if you've had a fall, or if there is a history of heart disease in your family (or you have a history of it).
 MedicineNet (www.medicinenet.com/chest_pain