Looking at the neatly made bed, and then at the somewhat wrinkled shirt she was wearing, she realized she would have to wear the same clothes when she left tomorrow morning. If she slept in her clothes tonight, she had no idea what state they'd be in tomorrow morning.
Ultimately, she still opened the wardrobe, and as expected, there were his T-shirts inside. She hesitated for a long time, but eventually shook her head and gave up on the idea. How could she wear someone else's clothes, especially a man's clothes?
If the clothes were wrinkled, so be it. She thought to herself that early in the morning, she was going straight back to Felicity Lambert's apartment anyway, so with that in mind, she lay back down on the bed in her clothes.
Maybe it was because the bed was too soft, or maybe it was the change of environment, but even though Anna was exhausted, she tossed and turned on the bed, utterly unable to fall asleep.