Pink tint on the edge of the screen

I woke up this morning to reply some messages and i noticed a pink tint on the right edge of my screen. It only shows pink on dark grey backgrounds with low brightness, but since i only use night mode and low brightness it's always there.

The phone is a month old today, it's basically brand new. Since it's a really expensive phone i've been extra careful, never dropped it or anything like that. I don't know how long it's been like this since i just noticed this morning.

It's my first iphone ever and it i'm really frustrated with this problem.

I've changed the wallpaper and hard reseted it, but it's still there.

Is this a common issue? Would a replacement apply in this case?