I think in this song, when he says "If she only knew", he means that he actually does care for her but at the end of the day he's just a "bird" and he kept warning her anyways because he knew that was what it was. Hearing part 1 and part 2, it sounds like part 1 is a combat song where he wars between the girl and her telling him that he'll fall for her and him denying it. Part 2, its like he won, or he at least pretended to win and now its sad and she's crying and he's just shrugging his shoulders like "I told you. I warned you..."
I think in this song, when he says "If she only knew", he means that he actually does care for her but at the end of the day he's just a "bird" and he kept warning her anyways because he knew that was what it was. Hearing part 1 and part 2, it sounds like part 1 is a combat song where he wars between the girl and her telling him that he'll fall for her and him denying it. Part 2, its like he won, or he at least pretended to win and now its sad and she's crying and he's just shrugging his shoulders like "I told you. I warned you..."