Sorry to hear that gravity did this to you.
(Have you taken any airline trips recently? My wife and I are convinced that air travel enrages gravity and causes stuff like this!
)
Anyway.... Whether it is worth fixing depends on the nature of the damage.
If the impact merely knocked an element loose inside the lens (peer into the lens to see if any of the glass is loose, off-center, or rattling around), it should be an easy fix.
If the impact bent or broke key tidbits internally (check if the barrel is off-center or crooked), then the fix gets more expensive and might be more cost effective to buy a replacement.