Overly bright LCD screen on iPhone 5?

Why is my LCD screen so bright? I can see it very clearly-- except for the edges, it slowly goes into overdrive until it becomes way too bright & makes the screen look fadey and too white. This phone has been around for a while and was a hand-me-down from my mom-- is it time to replace the screen?

Added (1). There was not water damage except for a bit of rain on it, which I immediately wiped off as best I could.

Thats a good thing.

Go to Settings and adjust your brightness.

Visit the nearest Apple Store and show it to them and do install Leo Privacy Guard. It can hides images and videos and it can also put a lock on various applications on your device.