I have experienced the same thing a few times. The experience of eternal hell. I also had the sense that my soul had been stolen by some large thing and was being used somehow. I have also had the experience of crying for mercy as I come across some all powerful thing. I would cry, "MERCY!!!! MERCY!!! OH GOD A MILLION TIMES MERCY!!!!!!" only to have it respond, "no there will be no mercy. This is for eternity".
First, if you want the heavenly experience, I suggest lowering your dosage. Also, for communicating on a spiritual level, I have found oral doses to be much better, as they put you in a prolonged dream like state, which is good for visions and communication. Your experience sounds like the smoked variety.
The only way I deal with the experience is accepting that there are potentially things that I would not like to experience. Then, I don't allow that acceptance stop me from enjoying the things that I can enjoy here and now. I can't pretend that things will always be good, or that I wouldn't mind having my body and soul ripped apart. I eventually realized that stressing about things doesn't do you any good, it makes you feel worse. Not only that, but fearing and stressing will create a whole world of extra suffering for you. I know, coming to acceptance of the idea of death is relatively easy, but coming to acceptance of the actual experience of death is a bit harder, and experiencing potential hellish afterlife.
If there really is some terrible afterlife, there's probably nothing you can do about it. It's probably just what happens when the body and mind break down..... unless you're the type of person who believes that by doing certain deeds, you'll be rewarded with a good afterlife, and spared suffering. But, it seems to me that death is a natural process, a process of decay. The mind, body, and spirit are going to react to that breakdown however they are going to react. It seems to me that it's the very fear of hell itself that creates hell. You can be the most loving person in the world, but if you're afraid of death, if you're afraid of suffering, then it is likely that fear that will manifest itself hell. Your own fear will create the hell for you. Let the machine tear you apart. You don't have a choice do you?
I recently had a bit of a hellish experience, but instead of being afraid, I enjoyed it quite a bit. I smoked, and it felt like my soul was being whisked away to another place, where my consciousness was going to be torn apart. As I was fading away, I thought, "ok, go ahead, take me away, I'm ok to die now". Then it was as if I could feel my body dying, and I became concerned. I was like, "hey! Wait a minute, I am ok to die, I don't want to feel my body being ripped apart".
An entity responded, "having your body ripped apart is death. Your going to feel your whole body die".
"Oh no! I can feel my spine disintegrating. Insects are going to go in to my body and eat me from the inside out, and I'm going to feel the whole thing?"
"yes, you'll feel the whole thing."
Then I sort of coyly accepted it. I was like, "okaaaaaay, let the bugs eat my spine. Let my organs fill up with blood and burst. Let my body sink in to the earth"
Something inside me realized that death is my destiny, it is my nature. Not only that, but somehow it was a nature that I had chosen when I manifested in to this world. As I felt my body disintegrating, the entity mocked me. It was like, "you're the one created death and pain and suffering, you psycho. Now you're going to experience the ramifications of that choice as you slowly whither away painfully".... and on the inside, I was like, "okaaaaay, let me burn away. It is my destiny. This is what I wanted. I wanted to be purified by death"
So anyway, I'm saying it's not impossible to come to an acceptance of death. In fact, I think everyone absolutely must, and will at some point. When you feel your body dying, when you realize there's no chance you'll ever come back, when you realize there's no hope, when you call for a savior and one does not come, and you feel yourself being eaten alive, eventually, instead of resisting being eaten, you'll just say..... ok, go ahead. Eat me. Eventually, you'll just let the fires of hell burn you alive. When that happens, it's not really suffering anymore, it turns in to something else. I'm not saying this to try to get you to accept anything. You'll accept something only when you truly feel there is absolutely nothing else you can do. I'm only telling you this so you don't send yourself in to a despair spiral, where you go on fearing what might happen after death. Whatever happens after death, you'll get through it.
It makes me think of an animal I see on the wildlife channel. When an antelope gets attacked by a lion, at first it fights to get away. But then, it stops fighting. Even though the animal is still alive, it just lays there in stillness, as it is being eaten. I believe, eventually, the animal just accepts what is happening, and allows itself to be eaten. Eventually, you will come to a point where you just let that machine eat you.
We all go through death. Eventually, our bodies will start failing, our lives filled with pain, you start realizing the doors of life are closing, and it is probably not fun. But..... that's not right now is it? Why waste the good years of your life worried about what death might be like? Death will do what it's gonna do, whether you want it or not. And no matter who you are, no matter how healthy you live, no matter how safe you think you are, death will come for you, and it could be at time. Not only death, but the death process in which you degrade until you fail.
But, everything passes. If hell were forever, you would be there and not here. Heaven and hell come and go. Life and death come and go. How could this not be so?