Yes, use a nail or something to poke through and get a feel. Push it through slowly.

OR use a 'finder' that can detect metal. I have one that detects a whole range of things. Has saved me more than once as far as electrical is concerned. Almost cut a water pipe in my ceiling too when making channels for an electrician years ago.

You might have found a metal stud or an air duct not a pipe. Most pipes will be centered in the wall where a small nail won't hit them.

My wife wants some floating shelves in our bathroom. What is the best way to figure out if pipes are behind the wall? I know that there is at least 1 because my stud finder thought it was a stud and I used a small nail to check it bc of the placement. It’s a plaster wall. Thanks in advance.

Pipes behind walls