Thanks for the query to H.C.M. Forum.
Pain in the chest , that too on left side in heart , is a cause of concern.
As pain is also in back and on right side , so reason may be due to,
( hyper acidity i.e. gastritis
Of course may be due to heart.
You haven't mentioned the age and sex?
Male around 40 years are more prone to heart disease
, while female are more prone after 60 years.
Get in ECHO heart and blood test
Consult your treating doctor and get in complete tests.