Hi, I am new to this site and I was having some breathing problems lately. Before, when I was in school playing hard sports... It would feel like my breath is out of reach, my chest feels like it is caving in, and I feel very weak and can not do anything until I catch it. Now for the past month or so.. It has been happening regularly. My doctor says I do not have asthma. Since I work, when people come back from a smoke break.. I can not take the smell and my chest starts to hurt. So basically my symptons are hard to breathe, chest feels like it is caving in, feels weak in whole body, and I get dizzy (light-headed) at times. If you can help or have any suggestions that would be very helpful. I don't want this to get any worse.. Thank you