Should I study again next year or continue self teaching?

This is a hard question. I have been studying IT these last two years and I have learned the basics of IT as well as basics of game design, like bare minimum stuff. Basic definition of coding terms as well as what assets are, how to make audio, basics of creating bitmap sprites, etc. I am wondering if I should continue to study a Diploma next year (cost $9,000) or just self teach in my spare time from work. I am not strong academically and am worried I might fail some exams if I can't remember enough content, in which case I still have to pay the full fee. The course covers concepts such as object orientated programming, data structures, web development, etc. So I am not sure if it is worth picking up the programming subjects in the course for the future or just keeping my money and self teaching with the internet? I don't know where to go to learn the more intermediate knowledge regarding programming, data structures, OOP and so on. There are millions of resources out there but I have no idea if any of them are even any good?

What is the best solution? I want to work on my own 3D RPG for a long time. Not sure if its worth taking that shot or not.