Twisted Leaf

[PepperZ]

One plant has this strange twisted leaf all of a sudden. Happened over night.
 
It looks fine from what I can tell  but for some reason one leaf in the middle of the plant is vertical instead of horizontal.
 
http://imgur.com/zrXNmOa
 
Any ideas?
 
http://imgur.com/3C6S4sq Edit:Backed up pic.
 
Edit: They ended up returning to normal after a few hours if anyone cares. False Alarm.

 

[FiresOfNil]

Your plant is going through puberty, these vertical leaves happen, if a vertical leaf lasts longer than 4 hours, please call a physician.

 

[N8thaniel]

 

[alkhall]

They do that occasionally, not an issue.
 
If it bothers you, clip it off.
 
Otherwise, the plant looks healthy, I would let it go.