statistics for pre post self-rating scale (domain) [NOT likert]

#1
Hi, I completed a study (n=1) involving using biofeedback to alleviate/reduce physiological distress in an adolescent with psychiatric diagnoses and a history of sexual abuse. I used the Behavior Assessment System for Children 2nd Ed. [self-report adolescent] and was interested in comparing the Anxiety domain pre/post intervention. I have other statistics [effect sizes] but i am stumped as to what test i do to see if the reduction in her self-report [SS 71 to SS 65] is significant, or even how to talk about this...any help? i was told "visual analysis and bar graph" and i was like "huh?".

Please help!