I was told my ongoing chest pain is not cardiac related, need second opinion?

Hi I’m a 57 year old male non smoking in previously good general health. In late jan 2017 I experienced a nstemi HA I had two stents fitted and was informed my HA was mild with mininal damage my EF was 45. I felt good for about a week but then began experiencing chest pain again I returned to the ER and was taken to the Cath lab and was informed all was good. About two weeks later I again returned to the ER with chest pain I was given an echo stress test which I passed with no problems. My EF was 60. I was told my ongoing chest pain is not cardiac related. Since then I have still been experiencing on going chest pain with no answers. I have previously been diagnosed with ptsd and anxiety disorder which has led me to the ER several times in previous years with chest pain.
I know I can’t keep going back to the ER with chest pain but it’s hard to know the pain is now daily.
I have been given nitro to take but it doesn’t seem to do anything to help me with pain. The only thing that’s seems to help is Ativan but I know you can’t take this everyday. I guess I’m just asking for a second opinion. My GP is not to concerned as he believes my ongoing pain is anxiety related.