Hi thanks for your question.
There is an entity called as non cardiac chest pain
. It is diagnosed when no cause of pain is found and all investigations turn out to be normal. Since your pain is under left breast, APD that is acid peptic disease
has to be ruled
To rule out APD, consult a physician who may be able to perform on you upper G I endoscopy
on you. If upper GI endoscopy turns out to be normal a short course of pain killer is recommended, as once pain cycle is disrupted, sometime it can lead to permanent relief as cascade of pain inflammation, inflammation pain is broken and patients get permanent relief.
Hope this answers your question