I Dropped My Phone, Help!

I dropped my phone from maybe, 1 foot in the air. When I turned my phone earlier that day, half the screen was yellow and then the other half was covered in lines. The touchscreen still works; no cracks either. What happened? What do I do?

I tried the following:

1. Taking the siding off and resetting the phone. (Didn't fix the screen.) Which did work, so the problem is probably in the screen.

2. Having people try to fix it.

3. Taking the SD card out and pushing it back in.

I have a lack of knowledge when it comes to phones, so anyone please HELP!