That sort of thing is caused by a hardware defect in the monitor itself. If you are, or know of someone who is, a certified electrician you could probably fix it by making sure the guns were secured properly. However, monitors can store a lethal amount of energy for days after being unplugged so DON'T try this unless you know what you're doing.
Otherwise, now might be as good a time as any to start looking for a new monitor. Undoubtedly, major retailers will find some holiday or other excuse to hold a sale. Just be vigil for a good deal on a new monitor.
the picture on my monitor shakes really bad mostly on one side but a little on the other side too..any idea what is causing this and/or how can i fix it?