I believe you can be game designer if you actually take the time to learn the methods and pursue which areas you are strong at. If you like do art work, you could go towards to character designer, modeling characters and backstory and such. If you like to figuring out code and math related problems, programming is the best way to go, where you would code to make the functions of certain aspects of the game.
I would try Unity 3D, I didn't know much of coding such as C# but I learned while doing it. And I knew how to design and create art, so it helped me to create a mini-game.