Unless the Cabin Crew was injured by something flying....she should've been in the alert position, feet on floor and sitting on hands, head against headrest. Something odd there.
That you are obviously concerned about it is a good thing. You have learned something, you won't do it again, you'll tell the stories in the bar and anyone who talks to you will have that in the back of their mind when they stomp on the brakes next to make a turnoff.