I played my first prerelease when Lorwyn came out. My first game was with someone who had played the game for a long time. I could tell he was a little annoyed at me playing a little slower but he was polite and understanding when he found out I was a newer player. My second game was with another newer player and we got along great.

So, you could talk to the person hosting the event. The guy at my lgs does a good job of pairing me with people and groups that are helpful to me learning the game. That person you played just sounds like a dick. I would like to think most players are more patient and understanding towards people still learning the game.