I've been having difficulty breathing for a couple of months now. It's really bad and it comes and goes through out the day. The worst is about two hours after i wake up in the morning. I keep yawning to get enough air and my eyes start tearing and I just feel there isn't enough air. I also feel some pain in my chest but it's very light. I went to two different doctors and they both said nothing is wrong with me and to just take my vitamins. I do take them but it's not getting any better. Any ideas what's causing this?