30 Photos That Can Raise Your Pulse in a blink

You have a cold or fever.

If your pounding heart is accompanied by typical signs of a cold or fever, like an elevated temperature, coughing, and sneezing, this is likely the culprit. Battling an infection requires your body to work harder than usual, and that includes making your heart beat faster in order to fight for homeostasis (its usual stable condition) and kick the infection to the curb, Dr. Mills-Frazier says.