Every felt instilled with fear all of sudden?

One night when I was on yahoo, I was answered a bigots question about the existence of god. Before I could type, I felt afraid and didn't even know why I never felt this way before. This last for at least ten minutes so, sat there in my room trying to figure out why am I feeling this way. Then it rent away I was disturb, but I quickly thought it was just human instinct to be spook like that can anyone tell mean what this mean.