Good that you had the testing. But the question remains, what do they feel is causing the symptoms you experience? Unless they can relieve the symptoms or explain them by some logical means, I would think additional testing may be warranted.
Here is an article on non-Cardiac chest pain, it's interesting and explains why symptoms from other things can mimic heart pain. Click on the "Overview and Symptoms" to see the image and explanations. patients.gi.org/topics/non-cardiac-chest-pain/
Your doctor is likely correct, but it would be best to know what's causing it and for it to be treated to help relieve your anxiety on the issue.