He says the word “phase” to himself because he’s wondering if everyone’s right to tell him that its just a phase and that he’ll get over it. He starts this bridge by talking about how he has no idea how to win her over or “make up her mind”. Him saying that her lips are better than his are him saying that she is the stronger of the two and the one with more power so it will have to be her to end the situation (kiss this goodbye) because he wont give up easily. Then, he again talks about what he realizes every time he looks into her eyes.