Edit : The fingerprint there is mine.
I'll try to keep this short. I got my nexus 5 in december 2013. ~1 month later, power and volume button are not working. Brought it to my carrier, they sent it to LG repair center where they "reseated" power and volume connector. Less than a month later, while watching picture, screen go crazy. First it seemed like there was a lot of static in the screen. Then it was like when you put gamma to the max on a monitor. Took it again to my carrier, and two months later, they come back to me saying i'd have to pay 189$ +tx (15% here) to get it fix. I know the phone internal work, when i start it i have feedback and i also have feed back when pressing volume keys. I changed carrier and left the phone on the corner of my desk because i got a sony xperia Z1. I've decided to change the screen because i miss the freedom of my nexus, so i just disassembled the whole thing and i found out the back of the LCD screen, which is pretty much a mirror, is scratched a lot. Is it normal ? I've attached a picture of the mirror.