I have these way to often. I happen to have vivid dreams and since I'm always working on cosplay it happens to be on my mind a lot.
I've had every dream I think lol. I've had the one's where I was unpacking and I forgot to bring a crucial item to a convention. I've also had one where I was missing money.
some of the recent one's that I remember are I actually had a con nightmare at a con lol. When we went to bed my cousin went off to hang out with one of our friends and I don't know why but I had a dream that we were wandering around trying to figure out where he was all night long because he kept calling us drunk. He's never drank at cons or anything like that so I'm not sure why I had a dream about that. I even remember waking up feeling angry a few times then falling back asleep and continuing the dream.
I also had one where one of my friends friends make people uncomfy and he checks people out during cons. Just girls so I don't like to go by him but I had a weird dream where he was making all of my female friends angry, and upsetting them and everybody thought he was pervert and someone was going to punch him in the face then I woke up.
I also had another dream where we driving to the con on these big clouds or something I don't even know how to describe it and we had my Black Rock Shooter Canon strapped to the top of our car cloud thing and the sheet covering it flew off and LED lights were flashing on and off. Then a lot of cop cars and the swat team came cause they thought it was a real Canon and that we were trying to shoot stuff. They didn't believe us about the cons and they thought we were using fake identity's etc because of the strange clothes, makeup and wigs. I think I had the dream since I had a conversation with a friend as a joke about putting the Canon ontop of my car and timing how fast I got stopped lol.