Hello, I am a male aged 22. I am also a smoker and have been smoking for the past 4 ½ years on an average of 5-6 cigarettes a day, but I am trying to quit. In January 2021, I suddenly started having a sharp pain in my upper left back which intensifies when I breathe. It intensifies even more if I try to pressure or stretch that particular area. I have gone through 2 X-RAYS but my lungs were perfectly okay according to the radiologists. It has been around 2 years but the pain is still there. I am not sure what is happening and whether I should be worried?