SPSS Help! What tests to use?

#1
Hello friends!

I am currently analysing some data I have collected about some patients, which includes their demographics and scale ratings based on their therapy and the therapy outcome.

DEPENDENT VARIABLE: The therapy outcome. The outcome is their baseline pain rating minus their pain rating after the therapy treatment (out of 33). For example, a patient that has a pain rating of 33 and by the end of treatment, the rating was reduced to 20, the outcome would be = 13. Obviously the greater the number the better!

INDEPENDENT VARIABLES:
Participant age (scale)
Participant gender (nominal)
Therapist gender (nominal)
Therapist experience (nominal eg. have they treated this disorder before, yes/no)
Depression (nominal eg. depressed yes/no)

Which univariate tests shall I run? I'm guessing Mann-Whitney U for the nominal variables?


HERE'S THE PART I DON'T GET:

I have eight scales where I rated aspects of the treatment, such as the therapist and patient relationship, therapists warmth, patient input etc...

I used a likert scale of 1 to 7, 1 being very bad and 7 being very good.

For each participant, I have a rating for each of the eight scales. I am assuming the type of measurement is scale.

I have been told to do a univariate analysis for each scale, and then finally a multiple regression. How will I do this?

What type of measurement is my dependent variable, the outcome number? I am assuming it is scale, so I will need to use a parametric test? But which one?

Also, will I need to make sure my data is normally distributed? How will I do this?

Thank you in advance for taking the time to answer! Stats was never my strong point!