Im no expert, but I believe that happens becuase your core temperature is raised and your body is over heated, it takes a while for all that heat to work out of the body and in the mean time you will sweat as your body attempts to regulate your temperature. you felt cool becuase you cant feel the heat inside of you only on your skin. next time give your self a longer cool off period and do what you can to cool down your core (drink cold water)