The play button on my Apple Earpods start playing my music or pandora spontaneously when they are plugged in

I've been having this problem for a couple days now, and it's starting to get aggravating because I take care of my headphones and my phone, despite it not being in a case, and it's draining my battery so much faster than it should. I'm almost certain it's a problem with the headphones because it only happens when they are plugged in. I had my volume up with them unplugged for 3 hours, and nothing happened. If this is a problem that's been happening, they need to fix it, to be honest. I'm sick of going into school with pandora on, and closing it before class starts and having it play music almost the entire hour because my headphones turned it back on even though pandora isn't even open anymore. I'm also wondering how much it would cost to get a replacement if this is unfixable, because I really like the comforting fit of the headphones, so I would like to get another pair of the same kind of headphones.