Today as my first time doing DMT. It lasted about 7 or 8 minutes, but I achieved full breakthrough after 3 hits. I was in my friends apartment and we did it together. I did most of what we had, he did the rest. I hit the first one, held it in for 30-40 seconds, released, and repeated that two times. I only inhaled when I took another hit. I started seeing shapes and patterns after the second hit, but I went into the tunnel a couple seconds after the third.
After a few more seconds the tunnel turned into a door. The door opened and an entity invited me in. I went into a hallway with many rooms on either side. Everything was very blocky and square. Green and yellow were main colors. In all the rooms were different numbers of entities with different planes of existence.
The first one I went in showed me this universe, but something was different. The universe was dancing. A very flowy, calming dance. I exited the room, but something told me my earthly body needed to lay down. I told the entities I will be back, came back to my body, lied down, closed my eyes, and went back into the door. Three entities led me to a room in the back of the hall.
The place was dark. One held out a series of containers. One was open and they were telling me to take it in. I wasn't sure how to do that at first, but released my ego and felt it. Pure love. Empathy, happiness, love, all the same. Then they disappeared and told me to visit again and I came back.