Your profile
Your name, your picture, and how they differ from your Instagram ones.
Settings holds everything about your dmrabbit account, as opposed to your Instagram account.
Your name
What dmrabbit calls you inside the app. It is not shown to anyone who contacts you on Instagram, and it is not your Instagram name.
Your picture
Your dmrabbit profile picture is separate from your Instagram profile picture. Changing one does not change the other. The picture shown next to your connected account is Instagram's; the one in your account menu is this one.
Your connected Instagram account
Shown here, along with the option to disconnect it. See Disconnecting and reconnecting.