I've just bought ipod nano 6th gen. my old ipod nano wall charger doesn't seem to fit it? do i need a new one?

I've just purchased the new nano 6th generation but my old wall charger doesn't fit. I've tried it many times but dont want to force it. Do i need to purchase an updated charger. I know i can still use the usb cable to charge it for now but dont use my pc very often to keep doin it this way.