pain in chest bone

[vinky27747]

I'm 31 years old male. I've had a mild pain in the middle chest bone (left side and only at 2-3 cm area) for about 5 months. I’m not smoking but occasionally I am taking alcohol (frequency about once in a month). Two month back I got pain in stomach due to acidity and omitting then I was contacted doctor and it was ok but  the pain is continue even it is feeling more than earlier, and continue. Two months before feeling of pain was very mild and occasionally.
Just one week before I gone through all the checkups written by Dr. (ultra sound, gastroscopy, 2D ECHO, X-ray and blood and urine test) then Dr. said my lung is clear and my heart is fine and no symptoms of any disease, he also said that it is probably caused by acidity or gas. He has given some medicine and told me the pain will go away soon. But I am still having the pain.
Could it be the cancer or TV symptom even though he said I have clear lungs and no cancer? I don't have any other symptoms.
Plz. Solve my problem………
Thank you.