I don't think you should call her anymore, but what you can do is accidentally run into her at campus or in the complex and have small talk. You've called her like three times and she hasn't called once. I dont know that it necessarily means she isn't interested but if you keep calling and dont get a call back it makes you look desperate.

Play it cool suave cat, just wait til you see her next and be like so how about we go out friday to a movie. Make an exact date and time so she can't wiggle out of it. If she says shes busy ask her when shes free.

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One day the Moon said to me, "If he makes you cry, why dont you leave him?" I looked up at the Moon and said, "Moon would you ever leave your sky?"