Does anyone know why my Nexus 5 doesn't recognize most of the storage (16 GB) on my phone?

[AC Question]

When I turned on my Nexus 5 yesterday, the phone immediately rebooted and showed the setup screen, so I knew there was something wrong. When I completed the setup I found out that all the data was erased from my phone. In the notification bar it showed me that I was almost out of storage. According to my phone there was only 5 MB left of a total of 128 MB. Normally I would have 5 GB free storage of a total of 16 GB. I tried to wipe the cache partition but it didn't work. I even tried to perform a factory reset, but that didn't work also. Does anyone know a solution to this problem?

 

[B. Diddy]

Welcome to Android Central! Is the phone rooted or unrooted? Running stock ROM?

If it's as major a glitch as it sounds, you may have to try flashing the factory image: [TUTORIAL] How to flash a factory image | Re… | Google Nexus 5 | XDA Forums

 

[AtlasLion]

Thank you. The phone is unrooted and is running stock Android 4.4 KitKat. It's indeed a major glitch I can't open any of the standard apps that are left on the phone and when I reboot the phone I have to go through the setup menu again.