Odd music issue on iphone

I recently deleted some music I had imported from my itunes library to make some storage space for a new software update. Afterwards, the rest of my music began acting all funny: I can't really control what song I want to play anymore, and when I hit forward to see the next song, it starts scrolling through all the songs, almost like a roulette wheel, before finally landing on some random one and then playing that. Same thing when I leave it on play. It plays one song, spends ten seconds scrolling to some other one, and then begins playing that song.

How can I make my music behave and be under my control again? Seems like some sort of glitch. Re-booting did not help.