My friend, I believe you have had more than enough cardio tests to absolutly rule out heart problems.
I realize that you did see a mental health professional who does not seem to think it is anxiety or panic, however, you really do have so many of the classical symptoms of panic disorder that if I were you, I would get a 2nd opinion from another mental health doctor, one that specializes in anxiety/panic.
Take it from me, a fellow panic sufferer with a cardio-phobia. It took me several different psyciatrists until I found one that helped me.
The chest pain you describe is detailed in the classic book THE ANXIETY DISEASE by Dr. David Sheehan. It is called DeCostas syndrome, after the doctor who discovered this particular type of anxiety-related chest pain many years ago in ww II soldiers coming back from combat.
Hope this helps you.....Jerry