Why is my phone's screen is all messed up.

[AC Question]

I have a Lenovo s820. I hit it with my hand on the bottom right corner by mistake while I was sitting on my bed.( I didn't see it lying there.) Now the screen is all messed up. The brightness and contrast is messed up and the colors are dull. Also sometimes the left side of the screen fades black or horizontal lines appear from the bottom and slowly goes to the top. The screen keeps flickering and the edges of the screen is faded and shows the previous screen. The screen does have a crack on it but it used to work fine with the crack. I can still use the phone like I usually do and the. touch works perfectly fine. Do I have to replace the LCD? Please help.

 

[belodion]

A remote diagnosis is hardly possible but there certainly seems to be hardware damage of some kind.