Wisdom teeth getting removed scared out of my mind?

I could give less of a **** about the pain I'm scared to be put under! I had a bad experience with the same oral surgeon, he used this mask to put me to sleep and I couldn't fall asleep and everything got blurry and every noise got muffled and It scared the living **** out of me. He said he no longer uses that method but he says is now uses laughing gas and they inject a shot into that makes you high or something. He said I would be out but then again he said I wouldn't? I'm so confused if I'm going to be asleep or just high and not giving a ****. Any know what they usually do if they use a shot?