Unfortunatly, lack of control in lucid dreams is really common for beginners. It also happens to more experienced dreamers. Yesterday morning I had a whole dream spent running into walls, the insides of closets and refridgerators trying to teleport!! And I've had hundreds of LDs!

Beyond lack of experience it all basically boils down to the dreamers belief that they can do whatever it is they are trying for and the emotions they feel at that instant.

If you are really serious about mastering dream control I suggest reading The Nature of Dream Control by The Cusp, as that is the best guide out there.