Narcosis is exaggerated by three things: Dark, Cold and Stress. It sounds like you had all three here, so no wonder you felt a little "off". You had the fun kind of narcosis, the kind you can discern. How often have you heard a diver say: "I've never been narced." If they've been under 60 ft, then they've been affected by narcosis whether they've felt it or not.
Narcosis is mostly silent.
When you are impaired on the surface you know it by your inability to walk and slurred speech. Unfortunately, these two key markers are missing under water. Even with these markers, surface impairment is often ignored or missed by the affected. How many times have you heard an obviously impaired declare their sobriety? Your instructor might have told you fanciful stories about handing your reg over to a fish or some other such silliness as what it's like to be narced. That's a dis-service to you.
So while the "feelings" are kind of fun and give you stories to talk about, most narcosis events go unnoticed. In essence your problem solving ability is drastically reduced with every extra atmosphere. That's the real danger and you'll never notice it until something goes terribly wrong on your dive.
