Awkward situation

Been in the school library studying since 10am. Two hours later.. An acquaintance of mine shared the same table with me. "you're handsome" was the first thing she said to me. Panic and shock overwhelmed me. I feel AWKWARD. Then she smiled smittenly at me. Are her eyes smeared with poo? Oh please, I'm so ugly. Why would someone said those things at me? Solution: pretend not to hear it and do not look into her eyes when I speak. That worked! In my mind, I wanted to tell her that I am fond of & love & like & adore another girl. Would "she" mind if I tell my acquaintance that I'm deeply in love with "her" even if it's a one-sided affair?