Thanks for your query.
Left sided chest pain
can be due to various reason like cardic anginal pain, acidity, musculoskeletal pain
You must post whether:
1) pain has got any aggravating or relieving factors?
2)Does it goes to left shoulder or neck?
3) Does it increases on exertion?
4) have you suffered any trauma previously?
I think you must get an ECG done to rule out anginal pain. Rest are not too dangerous.