Running 12 miles

Most I've ever ran was 6 miles:
So recently, due to lack of really intense tennis players, I've decided to take on running. I've been consistently running about 6 miles, which is about one lap around Forest Park. But about a week ago, I decided to go running because I had finished class or something. After 6 miles, I still felt I had energy, so I just continued running. By the time I got a little tired in the legs, I was already to the other side of the park, so I decided what the heck, I might as well go around the whole park. Then leg kind of started hurting a little while later, I kind of wanted to walk, but decided if I walked, it'd probably get dark before i got back, so I just continued running until I ran 12 miles. The next 3 days my legs were soooo sore, and i had problems going into the sitting position (e.g. going to the bathroom). Note to self, don't be stupid again.

Later friend asked why didn't I take the metro. Oops, I had forgotten my metro pass and any form of money. Then he said I should've called and asked to get a ride...but oops, I forgot my phone as well. Lesson learned: Always have phone and money.