There's a "nightmare" I've only had twice as a stage manager. The first time was my senior year in high school, when I stage managed for the first time. I was super stressed on Monday, having little to no idea what I was doing, completely unsure of how to make the transition and work with my crew. That night I woke up, but in the dark of my room I thought I was backstage. I freaked out: "Why am I lying down? What is this bed doing here? We've got to get a HOUSE through this entrance: there's no room for a bed!" I started to fumble around, reaching for my headset, searching for a crew member to help me get my bed out of the way. After a minute I realized it was 2am and I was not in the theatre. I took a deep breath and realized I needed to stop letting the show stress me so much (it did get better and we had a wonderful opening.
Flash forward about eight years. I took an ASM gig with a two-part new original musical. We didn't get a music director or accompanist until halfway through rehearsals. Many of the cast members had other shows they were doing and so dropped in and out of rehearsals repeatedly (I had to fill in multiple times with many different people). We'd known from the beginning the show would have a revolve, but when we got to the space on Monday we suddenly found out that it was built differently than we'd been told, forcing us to reexamine how to stage certain numbers. I let myself get talked into serving as the virtual ME since the poor LD had almost no one to help him finish hang and focus. After the first (very, very rough) stumblethrough, I stumbled home and fell in bed, only to wake up a few hours later. I again assumed I was backstage, the show was about to start, and again, I flipped out. I couldn't understand how I'd fallen asleep backstage, why I couldn't find my crewmembers, where the actors were, and most importantly: why was there a BED in the way? How had it gotten on the revolve in the first place? Fortunately I came to before I woke up my roommates, but it was a sign of just how stressed the show had made me.