Lock Problems :(

A few times now, when i have been locking my car, i press the button on the door handle twice to activate the deadlock. Now instead of making the normal noise it is different and i believe not deadlocking? Its the same sound but instead goes on for 3times as long, like its maybe seizing up? Also, often at the same time, when im in the car the interior handle doesnt work? it just pulls but doesnt release the catch, i have to open the window and use the exterior one!

Has anyone experience the same problems or is it just me with the bad luck?

Cheers

Jay