I always fear that I fall asleep again after the alarm sounded and that I miss my plane or get off late and get stuck in a traffic jam. Don´t worry, it´s human and you are obviously well organised @okkatana
I always fear ive lost tickets for the train (hell, i do that on my journey home from work sometimes!) deleted emails that i need for reservations and that ive forgotten something important. 2 instances hold serious memories tho. Once i travelled to Leicester got there and realised i failed to take my chargers - easy fix, just a tad annoying. Second was i went to London with friends, ended up losing a lot of money (thankfully in the hotel) and got it back thanks to security and the barman...i rarely lose stuff but that scared me the most. Good luck on your travels, i hope youre going somewhere nice.