Pictures always help.
The part I'm talking about should be moving into and out of the hole indicated by the red arrow. Is there something that looks like the end of a regular flat-head screwdriver sticking out of the hole? Does anything move into or out of that hole when you operate the MF/AF switch?
If the little screwdriver bit isn't playing Pop Goes the Weasel when you move the switch, then the switch is broken. From the way you describe the problem, it
sounds like the switch broke while it was in AF mode. Probably just a little piece of plastic on the backside of the piece of the switch that you see from the outside of the camera.
The auto focus drive bit is spring-loaded, so even if the switch is broken and you just
gotta use manual focus or die you could always try pressing it back into the body and putting a piece of scotch tape over it.