I'm a 16 yo female and for the past couple months, i get tightness in my chest in the mornings. it's not bad, just a bit harder to breath. ?

See a physician: You need full evaluation by a physician. Any history of childhood asthma?

?PerceivedTightness?: I'm wondering if what you are actually sensing is atelectasis and it takes a few big breaths to open things back up. Quiet breathing allows for collapse of our small air sacs at the edges of the lungs (atelectasis) - during our waking hours we all will take an occasional "sigh" breath to help keep those sacs open. The more sacs that collapse the "stiffer" our lungs become. Just a thought.