99.88% of people in the U.S. named Nikki are female http://names.whitepages.com/first/Nikki. This line tries to hide the possibility that she slept with a woman—that plus the Ricky Martin reference (he was famously closeted for a long time http://www.rollingstone.com/music/news/yep-hes-gay-ricky-martin-comes-out-of-the-closet-20100329) implies questions of sexual orientation.
This would explain the title of the song—perhaps her confusion is partially rooted in conflicted sexual exploration, or adherence to the social bi/panphobic myth that bi/pan girls are all promiscuous. Maybe she feels pressure to like men only, or maybe she doesn’t like men at all.
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