I'd recommend these books:
-The Art of Game Design: A book of Lenses by Jesse Schell- This is a great book about how to look at game play and understand why its fun/engaging (not really programming)
-Game Coding Complete by Mike McShaffrey-This is another great book about what it takes to build a game and the fundamentals that go into it (more programming related, but at a high level)
Why are you waiting to learn a language? A language is just a tool to express your ideas into something a machine understand. Whoever advised you not learn other languages is wrong, for any reason. If you can learn one language, it can make leaning others easier. If your classes have some made up language for a test, knowing a real language can't hurt, it should be helpful especially if they're trying to teach fundamentals of computers.
BTW, you will never feel ready to start making a game. There is always one more thing to learn. Start now and build your experience base, even if it's not the perfect.