discomfort on the left side of chest

I have this situation where I feel discomfort, pressure/burning sensation on my left side of chest sometimes.

It often happens if I am stressed for a day or two. I feel this discomfort sometimes close to left under arms.

I feel better if I press/squeeze the part with discomfort.. I also feel little shortness of breath.

I dont know if it is acid influx or gas or anything more.

Feeling this discomfor makes me more stressful.

Any ideas what I am experiencing? I just wanted to get some ideas before I head to doctor.

Not all heart attacks produce this crushing sensation. I had a MI in
June 1989. It never was a crushing sensation at all. It was a burning pain in my left center chest. The second was in May 1998 and it was a burning pain in my "right" side. I've been having some problems lately and they are a burning pain in my right upper chest and right side of my neck. From what cardiologists told me there is no exact thing a heart attach feels like. It can be right side, left side, center chest, right arm, left arm. Most anywhere.

It sounds atypical for angina so we would call it atypical chest pain.
However, even atypical chest pains can have their origins from the heart. What risk factors or history do you have that would lead folks to suspect that you have heart disease?

Hate to disagree, but in my case (practically 100% blockage of right coronary artery) the only symptoms I had was a burning sensation at the base of my throat and an achiness in my left arm. No shortness of breath or sweating - just a slight case of dizziness.

For years I was on the lookout for the crushing sensation and put off seeking medical advice for my symptoms for a couple weeks since I'd not read about any burning symptoms - since the incident (angiogram, plasty and stent) I've read just a few sources that cite the burning. I've told all relatives and friends to also be aware that it doesn't have to feel like the proverbial elephant sitting on your chest.

Cardiovascular first, especially if you are older; or GI trace problems (ulcers, etc.). Heart attacks produce a crushing sensation, not a burning, but pain radiating to the left arm is consistent with some CV problems. Shortness of breath could be simple anxiety.

Report back when your doctor figures out what it is.

Mild MI can be nearly asymptomatic, but the classic heart attack does produce the crushing sensation (i.e., it is the most common perception).

My elderly aunt had two heart attacks and never knew it until later exams showed clear evidence of old MIs.

You are correct, Owen. This is the problem with "referred" pain and keeps us adult cardiologists busy evaluating all forms of chest, neck, shoulder, arm discomfort. Some folks (about 25%) will have only fatigue and shortness of breath.