I'm OK, You're...OK?

My friend Mirenchu is driving in from Boulogne to join me for dinner.
She calls me from her cell phone.
"Je suis OK," she says. "J'arrive dans 10 minutes."
"Okay," I reply. "T'es ou?"
"OK," she reiterates.
"Non, j'ai dit, 'ou es tu?'" I repeat.
"Oui, je suis OK." she says.
"Oh, aux quais. Okay!"

Who's on first?