There is a dull pain under my right breast and above the ribcage. what could be wrong?

Multiple possibiliti: How long has it been ere. Any injuries. Could be gallbladder, stomach, blood clot in lung, chest wall pain. Heart disease. See your doctor.

See below: This problem mandates a real-time (face-to-face) meeting with a doctor. A history has to be taken along with a examination as well as labs and other tests. Only after all this will his doctor be in a position to tell him what's wrong and what needs to be done to help him.