Wow. I'm getting close to digesting a recent retreat and was going to do a separate post, but I can pretty much say Ditto to everything Maya said.
It was a two week retreat and that was a few weeks ago. I especially relate to feeling giddy and close, making resolutions, a big event, and then big doubts. And after the big event I really relate to: "whatever I tried to focus on for too long just got too strong for me to handle. I thought my brain would seize at some point. " It was a mix of everything seeming like sychronicity, pride, and guilt. At a certain point, I just had to say to myself, "spend some time re-calibrating and grounding."
Like you, I've been talking and writing to help get grounded.
I felt very very vunerable during the end of the retreat and after returning home. Maybe some spontaneous raptures, maybe not. I've made myself chill out over the past few weeks and formally resolving "no progress, no drama". Soon I'll formally sit again, make new resolutions, and see how it goes.
It strikes me that longer retreats might be more gentle ways to do this work. I think it would have been nice to go through a few periods of concentrating then grounding, then advancing a little more, etc. That's about the only real observation I have that might be of benefit, or at least something I might advise myself if I went back in time!

Ultimately, no regrets but I feel like I was playing with fire. I plan on seeking a local teacher/friend if I dive in again with as much intensity as I did. Maybe that's the other observation I would make.
Hope this helps! Thanks Maya for your report!
Edit: It's not clear from above... I think my experience was a big A&P. Maya's after events sound different than mine.