Sorry if I sounded a little harsh there, but it's really hard when people come here and say "I've had / got a pain in my chest, what should I do". For starter's we aren't doctors, so can't make a diagnosis, although we can make some educated guesses as to what it MIGHT be. The trouble is, if I'd told you that it's probably gas, and it really was a heart problem, I'd really feel bad to say the least. So, the right thing to do from our perspective is to get you to a place you can be accurately diagnosed ... and not the subject of "educated guesses!" If you hadn't described the intensity of the pain as severe, I might have suggested an urgent trip to your doctor rather than an ER. It's a tough call ... but it is people's lives we're looking at here.
Anyway ... glad to hear the good news that it's probably nothing to worry about. Be careful on what you eat before flying and keep your stress under control