Horizontal Black Lines On Screen

I recently bought an iPhone 5c off of a friend. Seemed to work perfectly except for the top right corner was a little out of place. Suddenly I was getting dim flickering lines across the screen. It also seems that the screen is a lot less bright. I figured out that if I apply pressure to the top right hand corner of my phone, the lines would go away, but would come back once released (I tried placing tape there but it didn't help). Does anyone know of an easy fix for this issue? I tried ordering a case to see if it could permanently push in the screen, but I figured I would rather just have it fixed forever if I decided to take off the case. I really don't want to go to get my screen replaced for such a simple (or I presume) problem. I kind of figured it might have to do something with the wires connected to the LCD but I do not want to just open my phone without knowing what to do. Thanks!

~Henry