Bremsepedalen til bilen min

Jeg hører lyd når jeg tråkker på bremsepedalen. Det startet etter at jeg bremset og det kom et smell fra bilen. English version: Hi i was pressing the middle button yesterday. (See attached picture.) i suddenly heard a breaking sound and i felt a metal stick had been broken under the middle button. i can still change gear and drive with the car, but it come up a different sound when i pressed the middle button. The sound like pressing out som air when i am pressing the button. Do you know what is wrong is it? How much to change the small part under the button?