Well...the FIRST clue that it's anxiety is the simple fact that no one...NO ONE...has heart-attack symptoms for MONTHS!
That's just simple FACT.
So then...what is there REALLY to be afraid of???
The more you invent/imagine things, the more your mind will run with it.
Why? Because it's your brains' "fight-or-flight" programming kicking-in.
It's SO EASY for the brain to "run wild" with all kinds of thoughts & imagined pains, etc.
It's automatic. Anxiety is nothing more...AT ITS ROOT...than this simple realization.
It's MUCH harder to coldly look something in the face, and say "There's nothing happening here."
Once you believe that simple premise...anxiety will start to crumble away.
CBT helped me to confront my goofed-up thought processes that led to worry & anxiety.
(wow! I'm kinda starting to sound like Morpheus here...
! Forgive me!)