Hello, Whistle! Some of us here also do whistles -- in the form of flutes and other wind instruments.
One thing you may find very quickly in classical music is that it expects you to sit down and listen for an extended time. Most pop songs are 3-4 minutes long, jazz tracks may go longer (up to 25 minutes in the case of some Miles recordings), but classical compositions regularly take a half-hour or longer to play, and all of it's important. We speak of an "arc" of sound, and that seems a good metaphor for the progress of a composition that may have lots of important material. But I would encourage you to take the time. It's well worth it.