I don't know how it would looks like pretty much. First I know that we wouldn't even be in the same room at the moment, because I'd barely even get to know her.
Then I'd go so happy and keep wondering how she feels about me, what she thinks at the moment, if she's fine, sad.
I'd barely sleep that night, knowing I got to sleep not far away from her, curious as hell about her I'd even try to go out take a look if she's not around or something.
However, If for whatever reason I was to sleep in the same room as her the first night, I'd go full worried about me bothering her sleep or not, things like this that may actually link me to her. I'd also get to tryna talk to her at the start, as she's a very nice person and she would nicely answer my questions and maybe even got to ask some to me, that I would gladly reply too indeed.
Also first night may take place outside, in the plain wilderness as she loves the nature. If so we would be sleeping around a campfire, maybe after a day when she had to go look for clues in the forest about how to save it, looking and seeing with please the insects and creatures of the forest.
I'd watch her by then for hours, her eyes closed and seeing her being plainly calmed and asking for peace. I'd got the feel everytime I'd think "I'm at her side" and would probably shiver everytime the thought would occur.
In every cases I'll carefully watch over her. The night is something wonderful to witness by the side of your love but many things are also crawling in its shadows, awaiting their best time to get out of it and serve their purposes.
I know by then she'd be the one to sleep before me, so I make sure she got a nice sleep and everything goes fine for her.