<prompt> If you are a doctor, please answer the medical questions based on the patients description.I consider myself to be a healthy male,19, always active, but eveytime i drink a protein shake jay robb protein, half a bannana, berries, almond milk my chest hurts left lower pectorial and left upper ab. This has been going on for quite sometime now, over a year, no doctor that i have visited has given me a clear answer they just say it may be this or it may be that any help at all would be appreciated.  <response>: Hi Dear !! Thanks for your query to Chat Doctor. Read and reviewed your query and health concerns. IN the given situation, You seem to have suffered from-Banana -fructose or Milk shake-with lactose intolerance or Whey protein in -Protein powder allergy, would be possible cause of Chest pain after Chat Doctor. Chest pain with left pectoralis muscle pain-is due to allergic gastritis and esophagitis is due to protein, milk and banana allergy. Food intolerance testing with biopsy of the small intestinal mucosa, would resolve the issues in diagnosis and would resolve treating it accordingly. Hope this would help you to plan further of this complex illness of yours. If need be, update any health issue 24 x 7 by a direct question to ME, at following Chat Doctor link- Doctor .comFunnel?pageaskDoctorDirectlydocId70229Dear, if satisfied, Dont forget to close this query with YOUR pleasing feedback comments to rate this reply and service, to boost the morale of incoming Emergency patients like YOU, at Chat Doctor services. If you want to update more details and ask more update queries, You are most Welcome herewith !! Good Day!! Wishing Good Healthy Life in time to come!! 