Ever have one of those stories that starts out with, "I just saw the weirdest person. . ." or some variant of that? I know I sure have. And, so far, everybody I know has, too. And considering the percentage of people who both read this blog and know me, the odds are very much in my favor that you do.
Let's face it: people are weird. They do weird things. They say weird things. Sometimes they just look really funny. There's really no helping it. Some people are just off. Sometimes you simply don't have the context of the situation going on.
By the way, you are that person. I'm not saying you're weird or off (although if you're friends with me, you likely are). What I'm saying is that nobody knows your stories or the contexts of your actions. The conversations people overhear, the inside jokes you share to people on the outside, the perfectly normal things you like to do with your friends - all of those things are really strange.
And most likely, somebody has a story about you. You've got plenty of stories about "this one crazy person". That one crazy person is a real, live human being. Of course somebody else has a story about "this one crazy person" who happens to be you.
When you go looking for characters, don't forget to look at yourself. But don't look at yourself as a protagonist. Look at yourself as "this one crazy person."