hey,   Sorry to hear about your problem. I had exactly what you are describing, the first time i went into the ER I was 21, they couldnt find anything wrong with me and they all assumed I was just exaggerating and told me it could be stress. Don't you just love doctors and nurses. I went back the next morning because it woke me up, this time to a different facility. They diagnosed me with pleuresy. My lungs had fluid in them although I wasn't coughing. So they gave me an anti-inflammatory drug and sent me on my way after they did an ekg and xray and blood work, the whole 9 yards. Just 1 month ago, 2 days before my 5 year olds birthday, (4) at the time, I'm 25. I was at the grocery store and felt the pain, this time it was way worse and felt liek my sternum was being crushed, it was the worst pain I have ever felt in my life. My chest got tight, obviously i was freaking out and told someone to call 911 and I had my son with me, husband is deployed in afghanistan. My son is safe, that was the only thing I was really worried about. I passed out at some point between the ambulance and the hospital. I had a heart attack. The first two incidents, may have been MINI attacks, as my cardiologist mentioned they are warning signs. I was very healthy before, I smoked onlywhen I drank and that was only a few times a year and I routinely worked out and ate extremely healthy. I had a heart attack at a young age. So please, if you are having any kind of pain in your chest, even if the doctors and medical team tell you that everything seems fine and you are still having the pain, GO SOMEWHERE ELSE, get a second or third or fourth opinion, bc at the end of the day, you are responsible for you and even though they are doctors they make mistakes all the time and it can be your life. So please be careful and I really hope it's nothing for you! Be safe!