Left Side Breast Pain I Have Pain In Left Side Of Chest Under Left Breast Hurts To Breathe, Lessens With Pressure To Chest Cavity?

I have pain in left side of chest under left breast hurts to breathe, lessens with pressure to chest cavity? - left side breast pain

But I'm going to the doctor as soon as possible, it sounds like a heart attack? Every breath I could barely breathe without pain, please provide personal assistance or other.