The first two verses where Ariel talks to herself symbolizes her constant depression under the sea. She believes the untrue, mean, horrible and biased things that people say about her, yet she doesn't believe the people of the sea when they tell her things that are true and that they have evidence of which could be the cause of her depression. The whole movie is quite sad, to be honest. The only people that are being severely negative and impacting Ariel's attitude are the men in the movie. Her father criticizes her mistakes and wonders why she never obeys him. But if you were a teenage girl, would you be curious as to why your father kept you secluded from the world, or would you be a good little girl and never wonder why he kept you locked up in your room? I think most of us would choose option 1. So, her father doesn't have the right to negatively speak to her about her choices when he himself doesn't ever really put himself in danger. Triton doesn't know about the outside world that much and he still chooses to lecture Ariel? No wonder the little mermaid isn't acting so little anymore. Or maybe it's just puberty.