Little problem with Nikkor AF-S 18-135mm

My camera and the abovementioned lens experienced a little drop on the ground some time ago.
Since then, the lens has been experiencing a little problem:

Zoom works no problem, focus ring works no problem... until I set max zoom/focal length (135mm). At that moment, the focus ring focuses all way around, except the last tiny bits that should make me able to focus the most far away objects/scenes. It feels locked.
If I zoom out a bit, I'm able to focus back up to the furthest focal point. And interestingly enough, if I set the focus in that point and zoom in to the maximum, the focus stays there. I can adjust the focus ring to focus closer objects from there, but if I do so, I won't be able to focus back again to the furthest point, since I'm at max focal length.

Do you know if this is a known issue with small hits, and are there any known solutions to it?
I'm willing to do small fixes if they're not way too technical and apt to messing things up.