I am a girl and there is this girl that is all the time staring smiling and laughing when I am around.she has a boyfriend.I work with her.What do you think why she stares a lot at me?Do you think she likes me or something?

It could be she knows you and you don't recognize her.

Why don't you just ask her, "why do you keep looking at me, do I have something in my hair?"

Maybe she wants to be friends.

Maybe she admires you