When is a heart beat too fast?

A heartbeat is too fast when you just finished performing a strenuous exercise... Its beating too fast I think because it needs to pump the oxygenated blood all over the body... That's why you always catch your breath or breathe continuously :))

Sometimes it also happens when you are in front of "your crush" wherein the case is you intend to blush and freak out ^_^

It also happens when you're nervous... not only fast but loud heartbeat :)

-based on my experiences