I Was Unable To Fly Due To A Heart Problem

i was unable to fly due to a heart problem / panic attack? Lately i ve been having long-term pain in my chest, it doesn t come and go, i am taking medication for panic attacks, but when i tried to fly today my heart beat went up around 200bpm, i had chest pains, difficulty breathing and they wouldn t allow me to fly. i get this feeling anytime i get nervous or even just excited (like about a birthday!!) the doctor has me on a 24 hour heart monitor, what do you think is the problem? i m young, not pregnant, dont smoke, dont drink often. just i ve already been to the doctor and have medication for panic attacks, also been through therapy. but the pain in my chest is constant. say for half of every week/ i m trying to say i have pain even without anxiety. fear or stress seems to add to it, but i also get something when i m relaxed, just walking along.