Welcome to HCM
We understand your concerns
I went through your description. I suggest you not to worry too much. When every available test showed that you are perfectly fit, why worry?
People with health related anxiety
do doubt every doctor. They say they are not satisfied. You don't belong to that category. Bravely believe that every check is done and you are perfectly alright. Get motivated.
I don't think you need second opinion
. But if you prefer to take second opinion, it is fine. But pledge that you will not go for further checks if the results again came back normal.
Then, please consult a psychologist
for further psychological treatment. I shall help you through health care magic if you desire so.
Hope this helps your doubt. Available for further clarifications.