Sharp pain under in left breast comes and goes don't last long hurts to breath in achy shoulder that feels like it needs to crack. ?

Pleurisy: this type of pain with breathing is usually caused by a muscle strain between the ribs tho sometimes a rib can get slightly "out of place" - they usually pop back in hours to days. If severe, or lasting longer than a couple days, or if you feel short of breath now, see a doctor today. Otherwise, some docs and phys therapists can offer manipulation that can help this.

Chest pain: Please see your PCP if symptoms persist. You need to be checked to rule out problems with your chest wall, left breast, heart, lung, and left shoulder.