I am 15 years of age, and at least once a day; at completely random times I will experiance a sudden pain when I try to take a deep breath in, I will feel a pain which prevents me from breathing deeper. It last for about a minute, and I have to take quick short breaths. I was just wondering if anyone thinks that this could be a sign of something more severe, or if maybe I have an anxiety problem. I've also recently gotten pain in my left shoulder, which may or may not be related to the problem. Thank you for you responses.