Everyday for the last 5 or 6 days at least once a day after I eat, my heart starts racing, I get sweaty, nausea, sometime i feel dizzy. Went to ER they said heart fine not sure what caused it, heart went from 100 bpm to 147bpm and started going back down, did this several times. After i burped very deeply several time it stops. What is this and is it dangerous?