I have been diagnosed with costochondritis years ago that won t get any better and is actually starting to cause a lot of pain in my left arm and shoulder area. I was rushed to the ER last week with the most severe pain in my left shoulder arm and chest pain I ever had my lower left side if my neck shoulder area hurt also. I thought I was having a heart attack. After blood tests, several EKG s and a stress test cardiac was ruled out thank God. Ever since that incident happened last week. I cannot get the pain to go away in my shoulder or my chest and under my left arm. It ranges from an ache to a severe, sharp stabbing pain. I had an accident years ago that I think has made this happen, but for some reason it is getting worse now! I was putting my fake Christmas tree away in my attic and I fell through the floor boards causing the fake tree to hit me right in the sternum. I kind of landed on it like that when I fell. Problems ever since. Is this costochondritis or intercostal neuralgia? Thanks for your help!!