Little grayish things in my house. Bug nests?

All right so this is grossing me out. They are on the walls in my garage, 3 on the wall in my living room, 1 hanging in my kitchen on the corner of the ceiling, and there was one hanging on the back of my bedroom door. They are grayish brown, mostly gray. They are shaped weird, but they are all shaped the same. They are thinner at the top, then they get wide, then thin again. My friend thinks they are silverfishes but that makes no sense. I really want to know what they are! We are calling the exterminator but I need to know now. Thanks!