You've probably trapped a nerve in the base of your neck. It's common but really horrible as the muscles around the affected nerve get all inflammed and sore. Is it really painful/nearly impossible to move it to one side and or straighten it?
If so then you don't need a neck brace as immobility will make it worse. You need to take some anti-imflammitories such as ibuprofen and it'll get better on it's own. Keep it moving as much as you can, maybe sit with a hot water bottle on it, keep taking the anti-inflammitories and get the missus to GENTLY massage the whole neck and shoulder area.
Trust me, I'm a pro.
edit: this is where we find out his neck really WAS broken, and my advice to keep it moving kills him. If so, sorry benchez. You were a top bloke.