kerry park loop. i did a very routine maneuver to duck under a tree branch while running downhill and my neck and upper spine completely seized up and i couldn't lift my head up for like 30 seconds and i thought i was dead (jk jk).
i walked for a min to try to loosen it up and eventually i got going again. luckily i was only like a half mile from home.
neck still hurts a few days later, but only after sitting or when i turn when sleeping. other symptoms, which may or may not be related, include blurry vision in my left eye and chest pain.