And now, I will try to sleep but instead, spend the entire night wondering if I packed everything that I definitely already packed.

Make a check list. That always brings me peace when I got a bigbshoot the next day.

Yea, that definitely helps, but I always seem to leave a few gimmies off of it and then am like, "ok, I packed my laptop... but did I remember the power cable?"

Trello list. A card for every suitcase/bag. That way not only is it packed, but you know where it is.

Credit cards and passport- I'm sure you already thought of this, but I usually am scrambling to call the banks to let them know I'm using my cards in different countries. Was surprised Thailand was ok but China wasn't for my Chase cards.

Toothbrush?