here in NY which is in the USA what you did is called meditation/visualization/and in psychology terms is called self hypnosis...

you used your imagination to consciously /willfully create a visualization of a non existent inner world as a way to calm your self down..and it worked...you were so calm that your muscles were relaxed and you had the sensation that you could not move...

here many people do this for stress reduction, my yoga instructor teaches it, and my sister went to a psychiatrist to be hypnotized in order to stop smoking and she and the psychiatrist did the same thing....he relaxed her until she could not move and then helped her to imagine a calm place where she can take her self to when ever she felt the need for a smoke.

lets use a common thing first to understand what switching is like....everyone has to breath so lets use breathing...

a person automatically breathes. the body does it for them. no one controls it...sure you can consciously think about your breathing and change it some times by focusing on your breathing and make it slower or faster...but what happens when you suddenly get triggered...lets use something that has happened to everyone at some point in their life....someone scares the living crap out of you as a joke, jumps out at you and yells screams at you....what happens to your body...it automatically reacts in what ever way your body handles that...some people scream and run the other direction, some people hold their breath some people pass out....

my point is people dont walk around thinking ...so and so is going to scare the crap out of me in a second be ready to hold my breath, be ready to scream, when they scare my Im going to lay down and create an inner world, Im going to pass out, when someone scares the crap out of me Im going to lay down and let an alter come out...

the reaction to someone scaring the crap out of a person is automatic, its not something people consciously plan.

because reacting to a trigger (getting the crap scared out of someone) is an automatic reaction dissociating is an automatic reaction to a trigger, which means switching into an alter is an automatic reaction to a trigger..

sure people can plan in their imagination and pretend they are switching if they want to (not saying you are doing that, I know some people who have tried to do that) but doesnt make it happen....the word treatment providers here in NY use for this kind of thing pseudo alters/false alters. basically it means the person has willfully/consciously created an alter or willfully/consciously acted out what they think is switching into an alter for attention or because they want to please their therapist.

the distinction between pseudo alters/pseudo switching and DID type switching is as the DSM states....the alters take control. the host does not control it in any way.

using the situation you posted a switch in to an alter would look like...laying in your bed you hear the fighting begin and your body immediately and automatically goes through its "scared the crap out of you" automatic responses and immediately an alter takes control. theres no planning out an inner place or control on your part. you wouldnt have had time to plan out a non existent inner world into existence.

my suggestion if you have DID talk with your treatment providers they can tell you what happens when you have switched during your therapy sessions...one thing about therapy is that at times you have to talk about triggering topics, because of that people with DID do switch into their alters during therapy automatically until they learn how to stay focused/grounded and then they have no need to switch into alters because they are capable of handling triggering things on their own..

another suggestion...since using visualization/self hypnosis has helped to calm you, keep using it any time. it wont create more alters or more dissociation or create an actual internal world but it is a grounding therapy approach that is used here in NY to help people with anxiety/depression/ and other things too. the more proficient you are in using this calming and grounding approach the more control over your dissociative problems you will become.. and who knows maybe by using your visualization technique you will no longer dissociate into your alters. may be your alters will understand you now have a way to take care of your self during triggering things so they are no longer needed and will integrate /become one with you. the end result you may not have to worry about switching because it may not happen any more once you perfect this visualization that has worked so well for you.

keep up the fantastic self nurture/self caring work.