I try to explain it this way: Traditionally, theater folks (actors, dancers, musicians, etc) often get the jitters just before a performance, even if it's the same kind of performance they've done for years. One theory is that the theater folk burn up all the nervous worrywort energy beforehand, so that they can concentrate on their performance once on the stage.
In my case, 'the stage' can be any organized event (like conventions) where there is lots of preparations beforehand. So, I get all anxious, my ADHD becomes more pronounced (or at least more obvious to me) as I try to remember everything that needs to be done and/or packed, trying to find things that flash briefly in my memory and then vanish in the quagmire (where are my RioVolt earphones??!) and often move so fast I cause more damage than good in getting my things together. I invariably overpack, but then again I have so many interests and activities that the junk I pile together is often used, so the packing is justified. Or at least rationalized.
This time, however, I don't seem to be doing that. Maybe it's because I'm home all day, so I don't feel rushed for time. Maybe it's because I'm not a dealer or a staff member of the convention, and I'm not bringing any costumes or blacklight/rave-party toys, so I'm not racking my brain with a big checklist. Maybe, after the events of last week, I just don't care. Maybe a little of all the above. All I'm packing is a reduced art supply kit (metallic gel pens are my friend!), some clothes, and a couple of pieces of art for the Art Show. It may actually all fit in one check-in bag, scary an idea as that is.
I'm looking forward to a Tuscon Autumn, where the weather is in the high-80's instead of blustery New Jersey's 50's. As much as I like the pretty autumn colors of the Northeast, I'm still a desert-raised cat so this should be pleasant -- barring any surprises.