My evaluation of your dream. Could be TOTALLY WRONG.
What I think things mean:
Therapy: (I am evaluating myself - shows you are in a state of better self understanding)
Male therapist: (the male is myself or my impression of what men are or mean to me - I might be evaluating myself, or I might consider evaluation of myself leaves me weaker - male suggests strength - STRONG / THERAPY = Growth I cannot turn away from)
I do not know this therapist well: (I am not sure where therapy will take me - I don't know what to expect from strangers).
Pillows/sheet: At therapy, I will be vulnerable. (I am vulnerable when it comes to sleeping or sexuality or intimacy or therapy).
He sat on the couch: ( I notice he sat on the couch which means, I want to pay attention to how my vulnerability relates to the intimacy of sleep/sexuality/therapy, intimacy.)
I was talking to him initially: (I pretend to ignore when things make me alert, and try to pretend everything is fine and try to focus on my goals.)
totally black space: (I went into myself, because I was in touch with my deeper subconscious because there are places and things about me I ignore and do not explore.)
Rocking back and forth: (In touch with vulnerabilities and offering self comfort.)
patiently staring at me, 30 minutes, bandage, head: (a few interpretations: but it seems to me this: I was vulnerable for a time in my life, but therapy has helped and is helping me or, even if I am vulnerable, I will come out okay)
Kind look, calmness, come here, squicks: (Myself or another person who offers me comfort for my vulnerabilities is being too suspicious. Seems that you have deep trust issues, and possibly little tolerance for yourself being vulnerable 'weak')
You being on the floor, and the table have significance in my opinion because you always keep yourself low: (lower is the vulnerable position - child postition- and the table was significant -
Table Dream Interpretation - Dream Dictionary - Dream Meaning - explains table in a believable way - basically authority or judgement)
taking off pants but still had pants on: ( transition from suit to white pants and white undershirt - although the white pants and undershirt are not the material of a gi, they are the color, and they didn't remind you of pajamas or I think you would have mentioned it - transition of authority to relaxed - it seems you consider boundaries of social and private to be rigid. That is a self reflection - are you judgemental when you consider yourself or other people acting too unprofessional? would you view someone wearing shorts to church doing something wrong?)
came up behind me/nude: (behind instead of in front might mean, you fear if you are not vigilant, people can sneak into your vulnerable area - not physically, but also emotionally or mentally - you like to watch people, what is going on etc - you like to feel in control and not let people surprise you- you fear or expect people can fool you, which is why they can 'come up behind' )
younger/ stronger/ eye: (You consider strength to be seen in muscles or in willpower - you believe you can see peoples strength and judge their danger by stereotypes)
the take down you almost expected, but stayed semi-upright and everything about that was a fighter poised to respond. (Sounds like you have had enough training to know that you allow the person to back away before you will attack - that is better then the untrained wild response of someone not at black belt. Remember, training teaches us not to respond unless necessary. As frightening as the experience, it seems you know you can handle yourself.
Your awake evaluation that you should have attacked seems to suggest you still fear you will allow yourself to be victimized - but actually the entire dream seems to suggest you are so vigilant that in any circumstances you will be alert and ready to respond.
If the dream stopped there, I would understand. If it continued and you didn't share, then my final opinion would possibly vary.
In my opinion, you have incorporated your martial arts growth, with a sort of therapy and you have come to the point where you know that when vulnerable - you will defend and attack if necessary. It seems the scenario of being vulnerable still worries you, but overall you will respond when provoked - but not overly so.

Just my thoughts.