Hi crumbly_rain
I feel for you so much as you face such an upsetting and confusing time in your life. It can definitely be distressing to different degrees when we've got no idea what's happening to us. If there's one thing most people have in common during such a time, it's the need to question what's going on and the need to find answers or better define what we're experiencing (so that we can relate to it).
Based on my own personal experiences over the years, I've come to see things from a variety of perspectives. While I have an interest in psychological perspectives, biological/chemical perspectives and natural or what some may term as spiritual perspectives, sometimes I like to take a step back and observe from all 3 points of view.
I've found, when it comes to trying to work out what we're experiencing, a lot depends on who you talk to in some cases. Mention to a psychologist or psychiatrist 'I'm experiencing depression, anxiety, depersonalisation and derealisation (amongst other things)' and they'll most likely say 'You have psychological, neurological and chemical issues that we need to address'. Speak to a spiritualist and they may say 'Ahh, these sound like some of the traits of spiritual emergency, something we need to address'. While 'spiritual emergency' may sound seriously woo woo, it's actually in the DSM 5 (Diagnostic and Statistical Manual of Mental Disorders, edition 5). Btw, when it finally become included, only in the last edition of the manual, there were a lot of disappointed people. This natural condition is regarded as a psychological condition, in the DSM 5. While it does have some psychological elements to it, it's not entirely psychological.
I think there can be the temptation to jump to conclusions in some cases but I've found it pays to consider the circumstances we face. Under the circumstances, is what we face naturally depressing or naturally anxiety inducing? For example, if we're a deeply sensitive person who's able to sense quiet easily, it's natural to sense just about everything and everyone that's depressing and stressful. So, there can be a need to manage and gain skills in how we feel people's nature, environments, memories, inner dialogue etc. If we're going through a mind altering process of development, it can be natural to gain a higher perspective. You could call this 'a bird's eye view' of our self. With such a view, it can be like observing yourself from a detached and more objective perspective, which can feel incredibly surreal if we've never experienced it before or if we're not taught how to experience it constructively. Depersonalisation is actually taught in some practices, such as certain yoga and meditation practices. To experience depersonalisation spontaneously, out of the blue, it can be incredibly distabilising and I can say this from personal experience. Certain 'grounding' practices can help.
In a nutshell, self understanding it's a massive rabbit hole. It definitely has a lot of surprising twists and turns. It pays to find the best people/guides to help us navigate. I hope you find the answers you're looking for, so as to gain a much needed sense of direction. 'Completely and utterly lost' is an incredibly challenging and sometimes distressing and/or depressing feeling, that's for sure.
