That's kinda like what happened to me In Hawaii back in '87. I was on a boogie board having the time of my life on about a 4-5 foot wave when in less than a second it fizzled out and I did a header directly in to the sandy bottom. Couldn't turn my neck very far to the left for over a year. I think I might have actually damaged something but never had it checked out, dumb on my part.