When a woman gets all cutesy and child-like when you interact with her, what is she feeling?

It could be nervousness because she likes you, but I used to know this girl who would play tease me all the time about my body and stuff, and it would make me nervous and shy towards her. She'd do it more and more - but then I found out she was a lesbian and was actually flirting with me & thought I was being flirty back, so I stopped talking to her. Not because she was a lesbian, but because the things she was doing were really sexual, and if she were straight it would have been just fun, but as a girl attracted to me it was like a guy doing it. So you never know, but you say you "know" she likes you so thats different.