Welcome to this site.
You have succeeded! It looks like a butterfly. 
Welcome @jessbernstein, very nice work. Seems cartoonish.
If you render image of your model or you want to use it in game engines, probably you can see your model only from one side. The reason is, It seems you’ve used planes to make it. You’ll learn more about What are Normals lesson I guess.
I just wanted to inform you because when I first start to model this kind of models, I was trying to export them to Unity and couldn’t achieve to make them visible. If you want to render or export your model, let me inform you much more. Otherwise, just stick with lessons.
Yes! correct.
In 3D a face has only one visible side, the side where the normal is.
The backface is transparent! But Blender doesn’t act like this, it shows also backfaces in the workbench (non-render). But a game engine renders only, so there a face has one side.
That is also why you have a solidify and skin modifiers in Blender. To give a face or edge a body to render.