I wanna know if this girl is joking around or is actually genuine?

So she slid in my DM's, said she wanted to talk.. I saw the message a week later ( I don't use Instagram that much), when I replied she flirted and said we would look good together and that I look cute. I found her attractive as well but I dunno what to say to her because she doesn't open up a lot even on basic things like hobbies and stuff. She doesn't even try to start a conversation on her own and i am really confused at this point. Do I start messaging her more or smth?
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+1 y
Chatted with her for a while, seems out she was nervous but was trying to get out of her comfort zone by flirting and stuff.. Her friends told her to stop showing interest that much 'cause apparently that would keep me intrigued.
I wanna know if this girl is joking around or is actually genuine?
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