i have been drinking coffee my whole life never had a problem but the last few weeks im having some type of reation my heart goes so fast it feels like im having a heart attack i get really dizzy and im light headed almost to the passing out stage i have been taken to the hospital twice once by ambulance because of this the doctors have given me all kinds of tests and nothing shows up im really scared it almost feels like im dying when this happens i drank a decafe yesterday and it happened again not really bad but enough to let me know i cant drink any coffee at all im scared of everything latly ,please give me some advice or anything that can help me.