iPad says its full storage but nothing takes up significant space

Hello,

My iPad says it has used 25gb (i have a 32gb iPad). Its a iPad mini w/ retina display (aka iPad mini 2). Its says 25gb used and 1.4 available. But when i go to manage my storage, the thing that takes up the most is ONLY 800mb. It makes no sense. Ive been through everything.

PLEASE HELP