You did well.. grabbing the arm rest though would be even better or finding and empty seat/strapping in.. my biggest applause goes to you in shutting the overhead locker when you got your bag out.. The amount of times people get something out of their bag and leave the locker open.. even for 10 seconds you need to close it even if the bag is going back in their... as you found out turbulance happens very quickly and very unexpectedley! The over head locker to me is like the farm gate.. leave it the way you found it!