Sudden jerks/spasms in shoulders and neck.

I am in exactly the same situation! I am sixteen. I started having theose twitches like eight months ago. Its like, i can feel when im going to have one, and when i do it's like a shiver down my spine. sometimes mu shoulders jump, and sometimes my neck jerks to the right or left. It doesn't hurt, but sometimes it is hard enough to crack my neck. It didn't used to happen so often, now it happens multiple times in an hour. I'm not really worried, but It's obviously not normal.

i have been experiencing this and my neck always turns left n i shiver .it lasts for a second or two.
my friend has noticed me twice when i got this n she laughs on it.
i am 16 yrs.
i get it 2 or 3 times a day.
i want 2 knw wat it actually is.