A few questions about DC's...

In a Lucid-Dream a while back i went into A&W a fasst food place. I saw my teacher and was staring at her surprised... Would she be considered my first DC

And another person in my dream is my friend dad? he only came into my dream once but would he be considered a DC?

If so why can't i have made up characters as DC's? or just meet a random person? Can someone help?

Thanks