Breathing problem. And feel relax.

I am suffering with this problem since March this year. I feel like i am not satisfied with my breathing so i need to yawn once in a while to satisfy my breathing. This problem occurs when i don't have any work or i am all alone or when i get less oxygen. I don't think so that it is related to asthma because i am able to breathe properly but need deep breaths. Sometimes i feel like there is something upon my chest. When i get involve in any work or surrounds by people i don't get this problem. Its like when i don't think it doesn't appears but it still exists but i just don't feel because i have another work to do. And sometime its increased and i feel restless. When i get this i usually prefer to lay down on bed or get sleep, it helps me to recover and feel relax.