Chosen Solution

I was swinging my apple ear buds around (bad habit I know) and they hit the top right corner of my Mac screen. They weren’t going very fast but there is a black splotch where they hit and the top centimeter of my screen has horizontal grey lines across it. The Mac itself is functioning fine but I can’t see the affected areas.

@aussi sounds like a broken LCD. The only way to repair it is by replacing the display. Here is the guide for it MacBook Air Models A1237 and A1304 Display Assembly Replacement