 [ Symptoms ] i have pain higher up on the left side of my chest and in my left armpit [ Disease ] hey this can be out of a ligament or tendon strain sleeping in an awkward position or lifting anything heavy may have caused this take anti inflammatory tablets analgesics with muscle relaxants apply local analgesic gels followed by hot fomentation do not lift anything heavy avoid sleeping on the affected side if symptoms do not improve you should get a mri done thank you