Recently, I've been running out of breath during PE in school, I'm 15. I noticed that i'm running slower and losing my breath quickly, this scares me because I was one of the fastest people in my class. I've started to feel a bit sick, with having back pain, arm pain, lower leg pain, and knee pain. I started coughing more frequently and my lungs feel as if its full of gas, like a smokey feeling inside. I've never smoked nor done drugs ever and the last time I've second hand smoke was 4 months ago with my grandpa. I've recently became more tired, and I started to lose focus. This is freaking me out sense I've been getting 8 hours of sleep every night, drink milk and orange juice. Another problems is that I've been getting sharp pains in my chest recently, like I got two today. I started wheezing and began breathing heavily. Oddly enough I wasn't doing anything besides sitting on my chair taking a test. So can you please tell me if there's something wrong or I'm just having a bad month.