But you're lucky, relatively speaking. If you were shot in the heart, your blood pressure would quickly drop, but it would take 10 to 15 seconds to lose brain function. In that time you could draw your gun, utter last words, or spend some time thinking about your unfortunate situation.
Caffeine can cause indigestion, which in turn may lead to heart palpitations. However, arrhythmia (abnormal heart rhythm) can also cause palpitations, and this condition is more of a concern. Seek medical attention if your palpitations last longer than two or three minutes.
The racing heart, chest pain, horrible anxiety, pounding chest, shortness of breath have returned over the past month. These episodes always seem to correlate with indigestion and last for months. I have mild scoliosis, pectus excavatum, flat feet, hypermobility, I have had IBS and GERD intermittently.