Having chest pains when breathing deeply?

For the last hour or so ive been having chest pains mainly when i breathe in deeply, i have had these before but not sure what could cause this. Around 2 years ago i had sort of a Coca Cola addiction that i stopped now, i've been quite stressed lately due to college, family things, i eat rather healthy generally, walk alot, generally healthy, so im not sure what could cause this, any ideas? (17 years old)