Well, Sony Xperia E dual white paper says that you should have:
Memory comprises approximately 650 MB of firmware, 750 MB of ?Phone memory? for downloaded applications and 2 GB of ?Internal storage? for music, pictures, movies and some application data.
so i have no idea what uses your memory. You can make backup of all your data and just reflash it with clean firmware using for example Flashtool , then root your phone and uninstall all unwanted apps. But it seems that your problem is solved now:
Settings > apps > all > album, facebook, instagram, any music/video streaming app > clear data
so i will close this thread 
That problem has been solved and thread is closed. If you have any other questions, please start a new thread. If you have any complains / opinions / suggestions, you are welcome to send them to Sony.yt Team using Private Message.