Thanks for writing your query.
Your symptoms are indicating more towards anxiety
, but still you should get yourself examined by a cardiologist again and get the following investigations done :-
1. Repeat ECG
3. Cardiac enzymes
5. Lipid profile
You should also get your blood pressure and pulse monitored for few days and especially at the time you are experiencing the symptoms.
Taking antacid like Omeprazole
20 mg once a day along with Domperidone
10 mg will be helpful in relieving your symptoms.
Also give yourself adequate rest and sleep.
Avoid working on computers continuously for long duration.
Doing yoga and meditation
will also help in relief of anxiety.
Avoid spicy/oily foods and donot miss a meal in addition to avoiding any mental/emotional stress.
Also avoid alcohol/cigarette, if taking.
If the problem persists, get yourself examined clinically.
I hope this is helpful to you.