I wonder if I might have actually enjoyed that Davo. We once took a night car ferry from Harwich to Hamburg. The sea was very rough. Mrs Mart was pretty scared and never slept all night. Car alarms kept going off, due to the movement of the ship I suppose. We had a small cabin near the car decks deep down in the ship.
Me? I slept through a lot of it. It was just like being rocked in a cradle. I also went for walks around on the enclosed upper decks, balancing the best I could. Things could be heard crashing about. I don't know why but I enjoyed the whole experience.