"I used to work at a childcare centre and when they brought in a bunch of balloons I completely freaked out. I ran into the office and called Mum and said, 'I can't get out of here - they're everywhere. What do I do'?"
Callen has this year been having treatment for her phobia, which has involved gradual exposure to her fear.
"They get me to listen to certain noises that unnerve me, from a distance at first and then the next week they might come closer and make the same noise."
She's still a bit jumpy but is less apprehensive about Christmas than she used to be.
The Herald on Sunday has come across several other Christmas-themed phobias, including cyssanophobia, the fear of kissing under the mistletoe, and ghabhphobia, the fear of presents or gifts.
Anxiety New Zealand Trust clinical services manager Emma Barker said phobias can cause genuine fear and distress.
"Say, for example, someone has a phobia of mice, if there is any indication of a mouse in the room. It would release adrenaline, stress hormones and that person would be desperate to get out of that room.
"That person would be hyperventilating, their heart would be pounding - all the responses we've evolved to get away from danger."
She said people could have phobias about anything - there's a phobia of peanut butter sticking to the mouth (arachibutyrophobia), and she'd heard of dinosaur and pigeon phobias.
She even encountered a child with a phobia of people dressed up after they saw a now-retired Santa display on Auckland's Queen St.
"It freaked him out so much he had a panic attack," she said. "There may be some predisposition in the wiring to having anxiety, but with specific phobias it seems they occur after a specific event, or it could be a learned thing.
"The woman I treated with a pigeon phobia learned that from her mother who had a phobia of birds in general."
Barker said some of the most common phobias were agoraphobia - the fear of being away from one's safety zone - social phobia, needle phobia and emetophobia - the irrational fear of vomit or vomiting.
GP Frances Pitsilis has treated several people with unusual phobias, including someone who could not sign their name in public.
"And I've had one patient who could not get out of the bathroom in less than two hours because of a fear of germs.
"If he had to shake someone's hand it would be a major challenge for him."
She has also met people with location-specific phobias, including a few with an irrational fear of travelling over the Auckland Harbour Bridge.