Something in wall when trying to hang shelf?

KY-Clay

You either hit a vent pipe, water line, or electrical wire. Considering it is a laundry room I would bet you hit the vent pipe as it is up high. Even if you punched a tiny hole in a vent pipe that is nothing to worry about. Water line is a different scenario. Look under the house in the crawl space for a water leak at that area. If none then you are ok.

rick29148

hit a electrical wire in the wall ???

CB

You probably hit a nail plate (protects electrical wires going through drilled holes in the studs). Search Nail plate to see what they look like (move the nail hole up or down at least 3 inches and you should be able to hammer the nail - if not find a new stud don't mess up what is behind the drywall.

Spock (rhp)

you maybe found either the water supply line or the electrical supply

Jimmy C

Electical wire. If you had damaged it, you probably would have received a nice shock. When I do that I use a stud finder to locate studs. Then I make a very small drill hole but I only go in just over half an inch, so I make sure if there is a stud there, or not.

Seann

Could be a person hiding in your walls