5.1 GB used when i only have 4 apps & 13 pictures, also I've deleted a bunch of stuff?

Hi, I've been having this problem for a while. I have an iphone 4s, says i've used al 5.1 GB and nomatter the pictures i delete it doesn't free up anything. I have only 13 pictures left on my phone, and i've gotten rid of snapchat and instagram. I only have 4 apps left, 1 app thats 1.2 GB and another thats 821 MB, twitter which is 171 MB, and a music downloader app thats 162 MB. I've deleted all of my messages, deleted pictures, cleared most of my contacts, and gotten rid of a ton of music on my phone. How can I fix this?

Deleting your files doesn't delete everything. Apps leave traces behind as do regular files. I would do a factory reset. Sounds like you have stray files on your memory.

Make sure you cleared the recycle area for your photos.