When I learned about Object Oriented Design for my first courses in Java, I sat down and read a book about Java for about 5 months. Then it finally clicked and all the theory I had read over time about how OOD works, suddenly made sense and I could pretty much utilize it all from the get got. It was the same concept I wanted to apply to learning Data Driven Design.
The thing is that despite a similarity in names, object-oriented design and data-driven design are different classes of concept entirely. The former is more structured an idea than the latter. I'd also challenge your assertions regarding your understanding of OO at that point in time, because many academic programs focus entirely on the wrong parts of OO and without using it extensively on real software, you don't really build up a true, "battle tested" understanding. One can acquire a passable understanding of a concept through books and other references, but until you really start using things in practice you have no idea how much you don't know you don't know.
I just really hate the notion of starting to code something and have no one by my side to consult with over it. Which is why I like getting taught by teachers rather than reading books or courses on the internet. If I make things wrong from the get-go and learn nothing I feel I've wasted my time.
You really need to disabuse yourself of this notion. Making mistakes is a critical part of learning and if you try to avoid it, you're only holding yourself back. Build games, and when you have questions or get stuck, you can ask people on the internet. Stop being afraid of doing it wrong. Everybody has, everybody will continue to do it wrong and make mistakes -- professional engineers who have been building games for ten years still make them happily.
You are holding yourself back by not trying to train yourself out of that pattern.