Hi i am experiencing chest area discomfort from past 4 days. Its gastric or acidity or Lungs related problem I am not able to make out. Climbing some 20 steps will elevate heart rate to 140. I had done CT scan Throax one month back and it was normal. Recently met Pulmonologist 3 days back and X Ray was done and even tat was normal. SPo2 level is 97-98 every time I check. I am taking medications for Gastric and BP from past 3 yrs. Covishield vaccination taken before 9 days. Is vaccination causing the effect or I am not able to understand. I have tried multiple gastric and acidity medications from past few days but not able to come out of the situation. Pls advise