Thanks for providing additional information.
I understand your concern and it's my pleasure to help you in every aspect.
As per your description,most likely you may suffer from Gastroesophageal reflux.
And your anxiety regarding heart attack acts an aggravating factor.
So you shouldn't worry about heart attack as chances are very low.
You should take OTC Zantac and Gas -X.
Also drink plenty of water.
Avoid spicy,fried diet and alcohol,smoking,caffeinated drinks.
You should elevate your head with an extra pillow while sleeping.
Deep breathing can be helpful.
If your symptoms 'll not improve then consult your doctor for a clinical exam.
I'm here to discuss further queries until you get satisfied with our conversation.
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