I get a tight pain feeling under an in my left breast, my armpit and into my shoulder blade, then it turns in2 proper pain if i hold my breath it eases?

See below: Shoulder pain could be from the shoulder or referred. Common referred sources include: abdomen, heart and neck. Shoulder sources include: arthritis, labral tears, instability, tendinitis, rotator cuff tears, bursitis, painful bony spurs etc. Shoulder blase pain can be from the neck or bursitis around the blade. Ribcage pain can be from rib joints. Its important to establish a diagnosis. See ortho.