I would say heteronormative as well. In her text universe, she is reproducing patriarchal stereotypes and suppression mechanisms with a veneer rebellion, which is actually nothing but a cloak for the phallus centred capitalism.
However, when I had the discussion with a friend earlier today, he proposed another perspective:
The queer thing was never her intention, because she was suffering from a false awareness, caused by a massive influence from media, school etcetera. But her lust is stronger than the hegemony. It is a taboo, but not a mistake. She's enjoying it! That's exactly accentuating the liberating in breaking away from the taboo.
The point is that she isn't asking her boyfriend for forgiveness, but rather just saying that she hopes it's okay with him. She doesn't want to give up on him, as she likes him, but she wants to be free to discover and explore more sides of herself, her sexuality and her gender.
The wrong/right part of the song, is exactly about her inner struggle, where the the internalised discourse is fighting her sexuality.
Again, lots of contradictions in her lyric. Another possibility is, that it's a cynical speculation aiming at both the heterosexual AND the queer marked. W00t.