My iPhone 5 won't sync to itunes?

Basically, I'm trying to sync my iPhone 5 to itunes, I did it once before to get all of my music onto it, but after that I synced my ipod touch also, and now NEITHER of them sync to itunes, nothing comes up or anything, it sits there like I didn't plug it in or anything, I need some serious help, if anyone knows what the problems might be I'd be so greatful if you could let me know, thank you.

Maybe your USB cable is broken or something. You should probably just ask on the apple forums instead. I'm only an enthusiast. The people there are likely to be a 100X better at answering this question than me.