Chatterbox: Chirp at Cricket

Guys, I need advice. I have a friend, let us call her Donut she is really nice and smart. Everybody compliments her, and she says she isn't smart. She is my best friend. I have known her since I was little. But now she is sort of getting full herself, she's not saying "Oh wow you are soooooooo smart, NOT". no she is not saying stuff like that. week ago we were typing our paragraphs and I was passing by her desk she turned to me and said, "Hey look at my science report,"  The paragraphs were greatly detailed and added evidence from our experiment and websites. "Wow you finished your report quickly!" I reply to her. Then she gives me this 'look' and says "(my name), Do you not know me? Uh This is only detail one!". I head back to my desk Slightly confused, "Why is Donut acting like this? Should I play along? Maybe she is tired of being told she is smart?" I go with that. Today at class, my friend was showing a digital report, It was time to leave, but we got a little secret view of his paraghraphs. It was really long and Donut said "It is even longer than mine!"  Another classmate told us that he had copied and pasted it on, "I knew it" said Donut, happily. "Yep, because you'rrrrrrrrrrrre the smartest!" I say in a Sarcastic voice.

Was that the wrong move? Please Help!