"Oh man, I'm jealous!" she's talking about his tail and the way he's set himself up with his dreamcatcher, not his visible exhaustion. That would just be weird.

"Can't sleep! Thought I'd come talk to the master." She smiles at him in a way that's harmless enough but probably a little too wise to his ways to be entirely innocent. "Guess you're not sleeping much either, though, huh. Having fun yet?"