Need help explaining!

Hi everyone, I have something going on with me that I haven't been able to explain.


I call it denationalization but it's not really, it's just the closest definition I could find. It started at my, well, kind of, first workplace. Side note: it was such a stressful job that many people quit after I did. Anyway, it first happened when I was sitting on my desk. First I felt dizzy, then, like I was slipping from mind, floating or smth. It has been happening to me for a year now (or more) and I even talked to my psychotherapist about it but she calls it just sudden relaxation due to overwhelming stress - mind simply can't cope with it and I slip away in an instant, when I reach my peak. Now that I'm trapped in my house due to the covid I've been trying to find help online but so far to no avail. It started happening to me at home even though I'm unemployed and got nothing to do. I have managed to make a full list of symptoms:

1. First I feel slightly dizzy and, that is important, as if I am a different person. Like, someone who simply had different life experience, made different life decisions. Person from another dimension - that kind of different. I start paying attention to some noises/smells in the environment as if they're suddenly important, meaningful to me.
2. Next I feel... How do I explain it? Weight in stomach? Not nausea, just a bit uneasy in my stomach.
3. Then I start recalling I do not even know what. Most likely, dreams. Flashes of images from my dreams. Patterns, colors, all abstract, meaningless. As I described it before - as if I am seeing nonexistent colors or shapes. Yet they're all so familiar... Like I've seen them in a dream once.
4. Next I often feel like my skull is contracting around my brain. A kind of change of blood pressure, although not really painful.
5. But after that I might feel a real headache.

This feeling of unreality can last for minutes or days and even a week. What is important is that I do tend to feel suddenly relaxed during these episodes and more concentrated. That is why I am not looking for way to get rid of whatever it is, I am just trying to understand. I want to know what causes it and why. What does it mean? What is my brain trying to tell me that I do not understand? I have been looking for answer for so long... I doubt I'll ever find an answer but regardless, thanks for reading my post.

"Depersonalization/derealization disorder is a type of dissociative disorder that consists of persistent or recurrent feelings of being detached (dissociated) from one’s body or mental processes, usually with a feeling of being an outside observer of one’s life (depersonalization), or of being detached from one's surroundings (derealization). The disorder is often triggered by severe stress. Diagnosis is based on symptoms after other possible causes are ruled out. Treatment consists of psychotherapy plus drug therapy for any comorbid depression and/or anxiety."

Thanks, I'll look into it. When you put it this way it does seem fitting...