We didn't have any animals on either of my shuttle flights. But NASA does sometimes send animals up in the crew cabin of the shuttle as part of experiments to understand how the animals are affected by weightlessness. Well, I'm not sure that I had any really scary moments. On both of my flights, everything went very well. The most anxious time was during launch, just because that is so dramatic.
Different astronauts sleep in different ways.
I slept just floating in the middle of the flight deck, the upper deck of the space shuttle. Some astronauts sleep in sleeping bags that are velcroed into one of the walls in the shuttle. Well, we don't get that much of a choice. And all of us wore socks all the time instead of shoes and socks. Plus, shoes are heavy, and you don't need them.