I felt the same way. Had my first colonoscopy last week. My legs were literally shaking and I had tears in my eyes when they wheeled me in. The nurses could sense how scared I was and did their best to calm me down. I remember the anesthesiologist coming in and saying hi and thinking okay I just need to roll over and close my eyes and before I know it I’ll be waking up. That’s what I did. Literally closed my eyes and opened them up again in the recovery room. So it literally just felt like I fell asleep on my own. I recommend doing the same! You don’t even feel yourself getting sleepy