I am a 19 year old college student, a smoker if that matters; For the past four days I have had increasing pain under my right breast, on my ribcage. It feels like a bruise/stiff muscel combined! As time passes, the pain increases and has spread around my side and onto my back. Sometimes it's so bad that it hurts to take deep breaths. Just today, pain on my left side, right below my breast and on my ribs, has developed. There is nothing visible, no bumbs, nothing strange happening other than the pain. What might this be!?