storm in there, whip your dick out and smack em in the face... lol but in all honesty i would just go talk to him. im sure he knows youll be honest with him from paying him for the work. just tell him you noticed it nicked and want to know if he knows what happened and your concerns of it turning into something worse. im sure he will help you out regardless for nothing. its not a long and pain staking process to fix a little chip.