door regulator question

[doctorJ]

I opened my drivers side front door yesterday and simultaneously heard a piece of metal hit the ground as the door kinda flew out of my hand and hit the car next to me - I picked up the steel pin that holds the door regulator onto the door jam, but the regulator ? ? , where did it go. Is it on a spring that has pulled it inside of the door? I looked around on the ground and didn't see the flat piece of metal that is on the passenger side door.

thanks


ps - checked and no damage to the car next to me.