Brief Answer:
More information needed to answer this question.

Detailed Answer:
Hello!

Thank you for the query.

Can you please give some more details answering the questions below:
1. Is this pain sharp and well localized or burning/squeezing like?
2. Does it get more intense when breathing or coughing?
3. Does it get better after pain killers?
4. Does it appear after physical activity?
5. Any shortness of breath with the pain?
6. Does the pain radiate to the arm or jaw?
7. Any other symptoms like nausea, belching, lack of appetite?
8. Do you drink lots of coffee?
9. Do you smoke?

I`m looking forward to hearing from you.
Regards.

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Brief Answer:
Esophagus inflammation can be the case.

Detailed Answer:
In such case, as the pain is strongly related to food intake, digestive system must be the case.
Gallstones or pancreas issues are known to cause back pain, arm pain and pain between shoulders. However usually such pain appears on the right side or in the middle.
It is also possible that esophagus issues like an inflammation or narrowing can give left side chest pain. If so, the pain should get less intense (just for a second) when taking a sip of lukewarm water.
And finally, any lesion which is located right under the diaphragm can give such symptom. Cough should be also present in such case.

I suggest you to have some tests done. It is necessary to have abdominal ultrasound, blood work, liver tests, pancreas tests, urine analysis done at first. Gastroscopy should be also considered.

In a meanwhile, you may try Omeprasole 20 mgs once a day. If this is stomach/esophagus issue, this should help, however the effect can be seen few days after therapy start.

Hope this will help. Feel free to ask further questions.
Regards.

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