Back pain under left shoulder blade when breathing

Patient: Hello,I am 22 years old and have been experiencing acute back pain under my left shoulder blade when I breathe for the past few days now, along with a mild joint pain and pain in my lower back, both of which I attributed, to a change in my exercise routine (I went jogging a week ago and am not used to this type of physical activity).The joint pain and lower back pain are manageable but the pinching/burning under my left shoulder blade when I breathe has just gone worst. Any idea of potential causes? Should I let it sit waiting for it to go away or could it be something more serious? Thanks

Symptoms: pinching/burning pain under left shoulder blade towards the center (spine) when I breathe

Doctor: