Do I look Untrustworthy?

Cust: I have a book in, you guys called me.
Me: Oh ya, right here.
Cust: But I ordered two books.
Me: It looks we're still waiting on one.
Cust: But I ordered them at the same time.
Me: Sometimes that happens. Especially if they come from different publishers. We can wait to call until everything is in if you prefer. We usually like to let you know as soon as something is in in-case you needed it.
Cust: Fine. I'll this one then.
Me: We'll call you and let you know as soon a the other one arrives.

No problem right? Fairly standard customer interaction? Yup. Until a few minutes later she goes through the entire thing AGAIN with a co-worker.
I guess she didn't believe me?