Share your experience!
The phone was gifted to me, the original owner said he accidentally put it in his pocket that had a wallet with a magnet clip, so it has like a big spot on the screen but it seems like the display was "pushing" against the screen. So if you press a little bit hard the spot becomes bigger.
Before turning off it gives me a blue screen and every time I turn it back on I have to select language and accept some warranty terms or something. Do I send it to replace the display or what?
I think it can be a software issue. Are you sure you're not in demo mode? Try dialing this code: *#*#73556673#*#*
I dialed the code and it shows a screen prompting me to activate the demo mode, so it's not activated now.
Strange part is, i was watching youtube and when i was turning the volume up the phone froze and the screen "glitched" but the little window with the volume bar did not "glitch"
I think it's a software issue then
I'd suggest that you do a PC Companion phone repair, this will do a clean installation of the latest firmware and will also wipe your internal memory. Back up your data before you proceed.
Open PC companion -> Support zone -> Phone/tablet software update -> Repair my phone/tablet (blue link style). Follow the steps given, do not connect your phone until prompted to press volume down while plugging USB cable.
http://www.sonymobile.com/gb/tools/pc-companion/
I'll try that, thank you 
No problem, keep us updated.