Hello.

Thanks for posting your query.

Any chest pain radiating to the shoulder blade should be evaluated thoroughly to rule out heart problems like myocardial ischemia.

There are other possibilities too like, a gall bladder stone or pathology of pancreas. Heartburn can be a possibility if you have history of acid reflux and yes antacids may offer relief in such case. But that cannot rule out a cardiac pain.
But I would advise you consult your physician and get a basic evaluation at least like
1. Blood pressure.
2. Electrocardiogram.
3. Some blood tests like blood sugar, blood counts, lipid profile, and liver profile.
4. Treadmill stress test (if needed as indicated by above tests.
5. Ultrasound abdomen.

These tests will confirm the diagnosis out of the above mentioned possibilities and clear your doubts. There is no benefit of wait and watch policy as it would only add to your stress.

Hope I have answered your query.

Regards,

---