key in the lock on the inside and now can't open from outside
 

Hi
left the key in the lock on the inside of the door to my flat and now can't open the lock from the outside, as the key wont enter the lock fully from the outside. Is there any way I can solve this without calling a lock smith?
the lock is one of these barrel locks. http://www.google.co.uk/products/cat...d=0CNIBEPICMAE
thanks for your time
kwisj

Look at the key and see if the key has broken off at the tip and is still in side the lock.
If not, a spray of grafite or silicone my loosen up the stuck pin inside the lock.