Meh, it's a number. When I was really young, I used to think there was an ideal age when things were "supposed to be a certain way," but after hitting different milestones, and having been flipped around by so many turnabouts in life, I learned to just say, "Screw it. Whatever is, is."
Besides, I've come to know 50-year-olds that enjoy life like 20-somethings and 20-somethings who are crotchety old yentas. Just take care of your skin, become BFFs with your stylist, and make like you age better than a vampire. For all the time spent growing up and learning enough about the world to break free of control, it's a challenge to feel young, but a waste to feel old.