Quote Originally Posted by Al Khalifah
I was merely explaining myself.

I laughed out loud and that and I don't know why. What does it mean?

Another American saying - it basically means that

peanut gallery
n.
1. The hindmost or uppermost section of seating in a theater balcony, where the seats are cheapest.
2. A group of people whose opinions are considered unimportant: "Pressure is building ... to force ... Alan Greenspan to cut interest rates and pump up the money supply. [He] has politely ignored these catcalls from the peanut gallery" H. Erich Heinemann.