Sorry to kick this thread again. Don't let people tell you it's NOT possible. If you're motivated, reasonable healthy, and take proper care of yourself (stretch, eat right, etc), you can ride that distance right away. I have a co-worker who has started riding about 12 hilly miles each way, every day, and he's ten years older than you. Your age is going to help you with your recovery time.

That said, if you chose to start out slow, with some of the advice from here, that's great too. I'm just surprised that some people would tell you it's not possible.