Good job! The goal is here is to keep pushing yourself. What will happen is that the next app will build on the skills you learn in the current app and so on.

Once you finish your first app, I'd look into some open source projects and see how they are built and learn from them. It accelerates your learning, but you need the basics first.

TBNR and the iOS Docs are a great place to start, but there's nothing like just jumping right in. :)

Also a word of advice: Making the app is only 50% of the work if you are expecting to make significant income from the app.