As a game dev you'll constantly be learning so don't stress on not being too good. I'm not either - but I find the limitations inspire me and force me to think more constructively. Start with a simple game with simplistic controls - but you'll still be amazed at what you can make! And it feels very fulfilling just completing a few projects. Don't sweat it - just apply yourself, learn and you'll create something special, at least to you if not anyone else :)