there are two entities in cardiac sciences
!) STABLE ANGINA - the pain relieves in 20 min on resting or taking nitroglycerines
2)
unstable angina in which the pain does not settles down on resting
as your pain is dull in nature a sort of heaviness on left side of chest it can be angina
your work hours are at night ...strss levels must be high a you say you suffered from anxiety
at a age of 24 you are hypertensive
you have not mentioned your
smoking habits
though at a agge of 24 cardiac cause is rare yet seeing your lifestyle we need to rule it out
broadly speaking your problem can be because of
anxiety
gastritis( because gastritis and heart burn also cause pain in the area where you feel it
or cardiac cause
i would advice you to go for
ecg
lipid profile
tread mill test (to rule out any lack of blood supply to heart during test)
2 d echo cardiography
cosult a pychairist and he may suggest you some anti anxiety pills in low dose called benzodiazapenes