Default [Q] Nexus 5 - Registering as a 16GB.

So I have a 32GB Nexus 5. I played around with it (flashed Android L, back to stock 4.4.4, rooted, ya know), and on the Bootloader, it says that I have a variant of the "hammerhead D820(E) 32GB" version, but when I go into my Storage in the Settings menu, it says I only have 12 GB left.

I just factory reset everything, so.

Is there any way to go back to 32GB?

Sorry, I'm a beginner to this whole thing..