I hope you have this Undoing experience, although it may seem quite scary. Many people talk about this experience beginning to occur after a major loss in life, a time where what they thought offered them some type of security suddenly was gone. Sometimes this experience begins spontaneously without any observable precipitating factors. Sometimes it begins when someone is involved in some type of altered states experience like yoga, or meditation, or other contemplative spiritual practice.
Throughout the ancient writings of the various spiritual traditions this Undoing is identified in many ways. In Advaita Vedanta, the Kabbalah, the Buddhist emptiness teaching, Gnostic Christianity, and modern non-dual teachers like Eckhart Tolle, Rupert Spira and others all point to this experience of undoing, this experience in which awareness arises and you know you are not your body-mind Ego state. Stanislav Grof, psychiatrist and the father of the Transpersonal psychology movement describes this as one of the experiences that can precipitate a spiritual emergency.
In Western psychiatry and clinical psychology this experience might be “explained” with definitions of pathology like depersonalization, derealization, etc.. (of course those who are labeling the Undoing experience as pathological are generally individuals who have not had this Undoing experience).
In any event no matter what labels (spiritual, pathological, or whatever) are used in an attempt to define it, it can’t really be defined because it is experience beyond the thinking, labeling, intellectual mind.