I dropped my Nikon Lens?

Everything see,s to work fine. I don't see any physical damage since it was in a bag when I dropped it. But whenever I autofocus, I can hear the motor running now. It will run every time I'm holding the autofocus and will stop about a second later after I release the autofocus. Autofocus still runs fast as usual.

?2016-03-15T15:32:03Z

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