Necks can just be bastards for no reason sometimes. You might've slept on it wrong, or bumped it slightly, or even just turn your head the wrong way at the wrong time.
Whooo knooows? I'm not a doctor, either~
Ya'know what's kinda funny? Looking at the conversation, I've compared our avatars. Both Miku, and yet both of them are so different. Yours is all, "Kawaii, ne, desuu~" and mine's all, "Come to meee~ Meow~" xD
Posted, by the way. Your no longer forced to stay. xD