What's wrong with the buttons under my laptop's touch pad?

The left button under the touch pad is supposed to work like the left side of a mouse- you know, just click on things. Instead, it's doing what the right button on my laptop does, creating a scrolling icon that lets me scroll down the page by dragging down on the touch pad. The right side still does this as well. I popped off the buttons and it didn't make any difference, so I'm thinking the problem is internal. My external mouse is still working properly with the laptop when I plug it in, but I want to try to fix the laptop button. Is there any way in it could have been reprogrammed through the computer settings to do something other than its original function? Or is it just plain broken? I think I have a warranty, so if you think this merits professional attention don't hesitate to suggest it. Thanks in advance!