Maybe it was an attempt at humour? Winding you up? Or, like stormyangels said, just a way of pointing out that you're both human. I wouldn't take this comment too seriously, as I doubt he meant it negatively. If my therapist said that to me I'd probably giggle

Interesting thought though! I bet therapists do have a sort of mental checklist of client behaviors that they could 'call us out' for... but I'm not surprised you've not found anything on it online - I don't suppose it would be very professional of therapists to publish such lists...