Why does my phone look water damaged?

Alright, so here's an odd question.

I dropped my phone yesterday, on a hard, DRY, concrete floor, and the screen ended up looking like this hours later. It started off as two purple bars on the bottom right corner, and I legit watched it get worse and worse as my day went on.

My question I guess, is why does it look like this? I put it in rice anyways, just in hopes maybe it will help or something. And is there anything else I can do at home to try and fix it lol?