I ran as fast as I could after my dog to try and catch him.
Did you not have a leash on your dog?
I usually don't have a leash when I walk him because he's never run away before.
You should make sure never to let your dog loose outside. They could get into some dangerous situations that way.
I've never had to deal with this before. I don't know what got into him.
Well it sounds like it all worked out ok for you, but hopefully this will teach you to use a leash. Letting your dog loose outside, even if you think they are obedient, can be dangerous since something may spook them and make them run off. It's not worth the risk of losing your dog.