Heh Jules, your story reminds me of a picture i saw back at my home in Thailand. My mum was still pregnant with me when she graduated with my dad (she was 30), and my brother was also standing there. I don't think there's anything wrong with mature age students, my old school teacher told me that when he was a mature age student, he use to copy answers from kids half his age lol.
I think you've made the right decision, by going out there, away from your comfort zone you can build greater confidence in yourself. I too am looking forward to uni life, there's a great gym and swimming pool at Sydny U which i'm enrolling in