I drive a 2007 civic lx coupe.

I was wondering what type of material the exterior was made of? I received some damage from a beer bottle thrown at me while driving through a neighborhood, cops said there was no way a beer bottle could damage my car that badly because the exterior portion of the car is made of metal. It does not feel anything like metal, it feels flimsy and cheap, almost like a plastic.

The location is right behind my door, is it really metal?

Its metal, but its made to crumple when hit. A low speed accident in a civic always looks really bad. They crumple to keep you safe. Not that a beer bottle is dangerous but if it was filled it could do some damage.