Yes, it is possible to have had a silent heart attack
would be shortness of breath, chest pains, etc. These symptoms
would be the result of a low cardiac output caused by impaired and damaged heart walls because of the heart attack. I had a silent heart attack about 7 years ago. You shouldn't be overly concerned about the results of an EKG.
Thanks for sharing your experience, and if you have any followup questions, you are welcome to ask. Take care.