Nope, not at all... I also changed my original fog light bulbs for Nokya Hyper Yellow pro halogen (2500k) H11. Since the yellow light works the best for me when it comes to fog.
Carefully reach behind the fog light and find the wires... follow them to the back of the lamp and carefully grasp in your hand. Then turn either clockwise or counter-clockwise (you'll see the bulb turn). It takes a little practice (and small hands), but you should be able to do it.
Good Luck!
-Tom L.