A fellow Australian, how cool!
It depends on the intensity of the trip in my experience, if I have a very healthy one I'll never know what happened during the first 5 or so minutes and usually ride the wave back down, like soulman said just knowing something incredible happened - towards the end of the trip I'll have these images in my head of bits of what happened at the start but I'd never be able to make sense of them or have the memory stick. But if it's a sub-breakthrough, which can be very powerful with changa, I'll usually not venture too far from consciousness which allows me to remember the whole thing in perfect detail.
I'm usually pretty good at remembering my experiences though which I think could be attributed to my fairly tuned photographic memory but also because of my ability to remember dreams quite well, which DMT helped and also helped DMT. But certainly remembering dreams and even practicing dream lucidity has a major effect on your ability to remember the experience I think. So if you haven't already maybe start trying to remember your dreams each morning before you get up, look around the net there are plenty of techniques such as keeping a dream journal. Also look into Calea, it's the perfect synergy with DMT and is great by itself in regards to dreaming.
However to be honest I wouldn't expect many people to be able to remember much from a full blown breakthrough. A friend of my recently sited that even on sub-breakthroughs he wasn't remembering anything, although this was after extensive use over a period of months the key point is everyone is different when it comes to how they interact with DMT. The only suggestion I have, apart from trying to smoke less and dream awareness, is to try out oral DMT which is allot slower and allot easier to integrate and as a result more likely to be able to remember. Other than that enhanced leaf is great for experimenting with different states within DMT.
To answer your other question no it's not uncommon to experience the same event twice, thrice and even frice on separate DMT attempts.
soulman said:
That was really really lovely. The initial rush was a little daunting but once it plateuxed, it was very slow, gentle and blissful.
I love that about changa, it's almost like turbo charged DMT. You can have a fairly normal dose and at the start the turbo of the changa will kick in and ramp the experience up to that almost breaking through level but then it drops off, and subsides into what would usually be the beautiful afterglow of a breakthrough but instead your in that state for the length of the experience instead of just at the end which also allows it to go much deeper and smoother and nicer and awesomer and ahhhhhh I love dmt enhanced leaf.