What is wrong with this girl?

So there is this girl in my high school, who i propsed, then she rejected me.
It's been 4 moths since this happened. Now i am starting to notice that she looks at me and then turns away when I look back. Sometimes she smiles at me too. This makes it a lot harder for me to move on. Girls tell me what's up with this girl?
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+1 y
Oh and I forgot to add this. Once when we were comming out of the school, I was chating with the boys. And then I saw her talking with her friends too. Then she gave me a quick glance and then turned away. Then after like a minute i caught her again looking my side.. but this time it was a whole different story.. the eye contact lasted for like 10-15 seconds. She just looked in my eyes. Then she just turned back to talking with her friends. What do you guys think this means?
What is wrong with this girl?
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