Been getting intermittent pain near lower left breast line extending towards left side of breast. ekg, echo, chest x-ray, blood work normal. when i press the breast, i can feel the pain under it. sometimes i get shoulder pain and jaw numbness?

Your body is talking to you! Listen & take good notes. When does it start/stop? Where does it go? What makes it better/worse? How long does it last? Medication helps/worsens? 
If you think it is something you eat/drink/do stop it & see. If better, go back again & retest until u r convinced it is something u should stop. Then stop it. Discuss with your Drs. You all will figure it out.