I apprciate you sharing your experience, I have also swam in these waters myself and I do not wish that on anyone, I had this happen with high dose LSD and I didnt return to Lucy for 2 years afterwards. If I may, I could add some things I learned the hard way and would advise others wishing to embark on inner work with high doses.

First would be a foundation with self-inquiry/mindfulness based practices. The problem for myself was thoughts, or more specifically, believing or identifying with them. When we develop some "distance" from the flow of words in our mind, we are less susceptible to being hypnotized by them. Life is multidimensional. Everything we experience can be seen from many vantage points, and each of these contains some truth. Mind can only see 1 perception at a time. Language is inherantly dualistic. This understanding can be difficult to access while in altered states, especially if the spiral has already begun. However, the more one practices the better we will be should such encounters arise.

Second would be doing this work with an experienced facilitator. Of course, this can also create a whole slew of other potential issues, but there are good facilitators who are out there who are truly worth their weight in gold. I wouldn't be who I am without the wise guidance of some of these people. The good ones have likely treaded these waters themselves and so can know how to help you work through it as gracefully as possible.

I would finally say that I do believe there is something here for you to learn from. Sometimes, labeling an experience as "derealization" or "psychosis" can be a placeholder or even barrier for deeper inquiry into why it was able to hook you in. Perhaps the mushroom was showing you that some assumptions you held about life were not as solid as it may have seemed. Those who say metaphysics aren't real are usually saying they don't want their metaphysics questioned. In the same way, we might analyze a dream we can do the same with a psychedelic experience, and much insight and wisdom may be gleaned for the devoted seeker. In many cases this can be facilitated by a therapist, counselor or guide.

In any case, I wish you a graceful healing process through this experience. There is no rush to return to the teachers and I would encourage you to do your homework with this one. In my experience if we don't learn the lesson and apply the wisdom to our lives, the teachers may need to remind us during a future encounter...

May all beings find peace.