What Could Be The Reason For Pain Under The Breast And On Left Of Chest?

I have right bundle block. My heart boctor has said I'm low risk for heart problem and I'm fine. But I get pains underneath my left brest in the center and I get pains upper left ofnmy chest and in the center of my chest. I'm worry that I'm having a heart attack what could this be? Also when inveterate mad or upset my chest hurts.I have had every hearttest they have an although I have right bundle my doctor says I'm fine and should live a normal life.