apple ipod touch is it possible to reverse updates

My ipod touch 5th generation running firmware 8.4 no longer allows me to operate my music app. as it did before. I am unable to change the bottom bar from My Music, Playlists,Radio, Connect; to Songs, Albums etc. as it did before. The top left shows a face in a circle which connects to accounts; it use to show "more" which enabled me to change the bottom bar. Can anyone help please?