can have multiple reason. I wish you must have told about the site duration intensity of pain.
squeezing and chest tightness
sort of feeling with pain at the left shoulder, arms, neck, jaw can be anginal pain....in this case urgent ecg and cardiac enzyme testing has to be done.
a localized pain which increases on deep inspiration, coughing, sneezing
etc can be pleuritic pain which needs antibiotic therapy.
pain at anterior chest at costochondral junction may be due to costochondritis
sometimes acid reflux
also causes substernal burning sensation.
other causes can be post traumatic pain.
in yours case, your age doesn't permit for anginal pain until and unless there is some underlying cardiac structural abnormality.
better meet your physician, get examined thoroughly......