Are you getting any unusual vibration? You may have lost the metal weight from the blade. If not just check your balance, pitch and tracking. There is no paint on the rotors so what you "chipped" is the protective plastic coating. You need to put a piece of tape over the crack to reseal it. Then you have to balance the pair again. An easy way to check the balance is with a homemade balancer. You can look at my pics and see what I mean. You should always check after any crash.