Honestly, I feel like this is fairly common. My classmates and I have frequently talked about how our minds go completely blank when we're in simulation or doing skills check-offs. Not only are they creepy, it's just really difficult to fake interactions with a stinking doll! It also doesn't help that you know you'll be watched by an instructor when you're doing sim or a skills check-off. That's a lot of pressure! I'm in my last semester, have probably done 10-15 simulation experiences, and I still get extremely anxious and do silly things every time I have one. Thankfully sims aren't graded in our program, they're just viewed as a "safe space to practice".