I turned my beloved Nook on the other night to discover a small, but extremely annoying bright spot right in the middle of the screen.

Its only visible with the Glowlight on, but I use the light all the time.
I have heard these happen sometimes and always hoped it wouldnt happen to mine. I bought the Nook back in Nov 2012 so its well out of warranty.
Is there any way of fixing this? Can I buy and replace the screen myself? I suspect not, but figure its always worth asking.