Maybe I'm the only one, but I see this as a guy who's always liked this girl but never really knew her, he just kinda liked her from afar. And she's never noticed him because she's had her own relationship issues to deal with or she's just not into him. And then they sleep together and the next morning she regrets it. So when she opens her eyes she realizes how much he really cares for her and he wants to hate her now because it was just a one night stand, but when her eyes open, he realizes he still wants her.
Maybe I'm the only one, but I see this as a guy who's always liked this girl but never really knew her, he just kinda liked her from afar. And she's never noticed him because she's had her own relationship issues to deal with or she's just not into him. And then they sleep together and the next morning she regrets it. So when she opens her eyes she realizes how much he really cares for her and he wants to hate her now because it was just a one night stand, but when her eyes open, he realizes he still wants her.