Welcome,
(If this gets TL/DR at any point, at least go and read the much more entertaining story linked at the bottom. And the quote in my signature. Those will be enough. But if you want a better cognitive understanding of what DMT can do, then read on.)
So here's my understanding of entheogens, and of meditation as well for that matter.
They're tools to help us become more aware of ourselves, to become more self-aware, and particularly of anything we've repressed. This is how meditation and entheogens help us heal.
Surely they can help us become aware of other things as well, but to lesser benefit in terms of healing. And since, unfortunately, that we are in need of healing is why we exist here, the various other awarenesses that DMT and other entheogens can bring us are of less value than the self-awareness they can bring us.
The primary way that being more self-aware heals us is through a process which psychology and neuroscience call "exposure and extinction". The mechanism of exposure and extinction is that by going through an experience, any experience really, we can gradually become less afraid of it. The religious and mystical traditions have their own terms for the process of exposure and extinction. In Christian mysticism for example it's been called "The Dark Night of the Soul." Jesus referred to it when he said, "Pick up your cross and follow me." Your cross being all your repressed negativity, which in his analogies we pick up by being like "little children", being "meek", being "poor in spirit" (i.e. not "spirited", meaning not egotistical), in other words he was telling us to keep our minds still. Buddhists speak of facing our demons by keeping our minds still.
Entheogens and meditation are catalysts for exposure and extinction, they accelerate the process so we can heal faster. And the most powerful of them, DMT in particular, can even provide us with the "exposure" itself, through scary visions and by unlocking our subconscious thoughts and feelings, so that we don't even have to be exposed to difficult experiences in our lives in order to get the "exposure" necessary for us to heal.
So, in this light the anxiety you're experiencing is a very good thing, it's really the way that the highest goal of entheogen use is reached.
I'd recommend some ayahuasca, either traditionally, or perhaps using full spectrum alkaloid extracts, as the latter makes it easier to titrate up to a dose that's sufficiently strong for more rapid healing. Vaporizing it, unless you've got changa and are willing to hit it hard enough, just isn't long acting enough to get the most out of it.
Sometimes we may not want this type of healing, so it should be pointed out that it's not optional. We just keep incarnating and going through terrible experiences until we expose and extinguish all the negativity inside us, because it's that negativity that's causing the terrible experiences to occur.
Until one becomes pretty self-aware it might be difficult to believe that our negativities, our negative thoughts and feelings, are causing the negative events in our lives rather than simply being reactions to those negative events. It would be a fools errand to try to convince anyone of this, but if one so desires they can find out whether or not it's true.
This may sound pretty "woo-woo", but reincarnation was taught by Socrates and Plato, by Jesus (he noted that John was the return of Elijah), and by many teachers in the East. Being a profoundly skeptical sort I didn't find any of that credible. After a voice that sounded like one would expect God to sound told me about a past life of mine once when I was experiencing full consciousness during deep dreamless sleep (a side effect of meditation), and after I realized that I still had a lot of the same problems now, and once I figured out how a lot of them relate both to that earlier life and to larger patterns in human existence, after all that all the anecdotal reports that reincarnation is real now seem much more credible. Again, not something I'd try to convince anyone of (I'm really very anti-faith), but if you really want it you can find the truth. (reminds me of the "The Harder They Come" soundtrack, with the truth "you can get it if you really want", and it does come a bit hard)
Best thing you can do is to just keep your mind as still as possible. See going through the fear as the necessary component of overcoming it, and see overcoming it as non-optional. If you ever find out that what I've written here is true you'll also find yourself chasing your fears, diving into them at every opportunity. I hope you make it there. Good luck.
This is a great tale of Ayahuasca healing by Peter Gorman, one of the bigger figures in introducing Aya to the First World. I don't agree with everything he believes, but the parts about "the doctors" and their effects is priceless:
https://thegormanblog.bl...h?q=the+doctors+rustling