You're complaining of left side chest pain
and you're a known hypertensive on treatment.
Any chest pain should not be taken lightly unless the cause is found.
This becomes all the more important due to increase cardiac risk with hypertension
If it is a musculoskeletal pain
than any movement and deep breathing will aggravate it.
If the pain is more central and towards the left and radiating to the arms than most likely cardiac pain.
Consult your doctor for more help.