I am not a composer but I do have a similar memory for sound. I can "listen" to music in my head very vividly. It can go on for quite awhile almost subconscious

I am not a composer but I do have a similar memory for sound. I can "listen" to music in my head very vividly. It can go on for quite awhile almost subconsciously and when it ends it often feels like someone else turned the music off, leading me wondering what happened.