Broke my OG screen

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http://forum.xda-developers.com – Hi everyone! My Optimus G fell off the table, and apparently it hit the floor with the right top edge of the phone, so that's where the screen is slightly cracked. The worst part is that the touch screen is now only working from the middle to the bottom of the screen. No touch screen upwards. I know that there must be something broken inside but what's up with the touch screen? Does any one knows how it works? If I had to replace the screen, can I do it myself with the proper tools? Is it expensive? (HowTos)