Hi LateJourneyer,
Great experience report! I think I've got a good feel of your trip, which seemed very interesting.
I also enjoy solo journeys, and I almost never have bad experiences, but I think it is generally safer to have a sitter present. However, having the sitter in the room with you can alter the experience and while it can be interesting, I really value the occasional trip alone with myself. What I have found to be a good compromise is to have a sitter present in another room. It is very reassuring when going for a breakthrough, for two good reasons. 1, if something were to happen to you during the trip (stumbling out the room, vomiting...), the sitter would be there to help. 2, if you happened to have a bad experience, you could integrate it by talking it out. Anyway, just my 2 cents.
I agree that this was sub-breakthrough. For me, a breakthrough is when you no longer have a human body and are no longer in the room where your body is. It can involve entities or not (some people have purely abstract breakthroughs), but in your case it seems you would encounter some. Another element that seems constant in my experience is fear. Losing your ego can be quite scary at first. The fear subsides quickly however, in my experience.
My advice for a future breakthrough would be: be prepared to be afraid, and be prepared to let go when fear arises. Also, if possible, have a sitter present. It just makes things a lot safer.
See you somewhere in hyperspace!
“How he could be a good user of LSD," I asked, "And know about the spiritual dimension - all that sort of thing - and still be a crook? I don't understand."
"Then it's time you did. Psychedelic drugs don't change you - they don't change your character - unless you want to be changed. They enable change; they can't impose it...”
― Alexander Shulgin, Pihkal: A Chemical Love Story