brake grind??

juhu…. so I noticed today that something with my brakes is really true! I had washed my car yesterday!Today I only drove with it again and I noticed that when I brake slightly, at the front left it sounds full as if it grinds, but really loud! the whole thing is not always, only once in a while! but brake he does quite normel1 ach yes is by the way a lacetti/1.4er with 95hp and 5 years old! thank you….