Odds are its facebookthis or photos ios6 tweak. Remove these tweaks then run iCleaner on its default settings. It should bring everything back to normal. Also, follow this link. Theres a discussion and then at the end i posted some more links to other threads. This problem is all over this forum. Whatever is causing it, this forum will help find the solution lol. It's such a common problem these days! Typically, removing those two tweaks and running iCleaner will fix it.
https://forums.macrumors.com/showthread.php?p=15203479#post15203479