I've tried to limit how much I say 'no' to you, attempting instead to redirect your attention away from whatever you might be doing that I'd exclaim "No!" to. I won't pretend I've never said 'No', or its variants like 'Don't!' or 'uhn-uh!' or 'Absolutely not!'. I suppose I should be grateful that your first would wasn't 'No', as I've heard is the case for many babies.
Perhaps it was my laziness the other night that really drove home the meaning of the word for you. I've been battling a sinus cold, and I simply didn't have the energy to keep redirecting you when you got into things that were potentially messy or unsafe. I started saying a stern 'No!' with an emphatic shake of my head before removing your hands (or whole self, as the case may have been) from the offending object or situation.
The very next morning, you started trying 'No' on for size yourself. At breakfast, I offered you a banana. "Nuh." "You don't want it?" I asked, offering again. This time your "Nuh!" was accompanied by a vigorous shaking of the head as you threw the banana on the floor. How about toast? "Nuh!" Eggs? "Nuh!" Yogurt? "Mmmmmm." Yogurt it was, then.
You seem to enjoy the newfound sense of power that comes along with 'No'. It's a powerful word, really. It can be used an expression of disgust or disbelief, a way to decline an offer, or a way to communicate displeasure with a current or proposed activity. You like it so much that you even enjoy practicing it to yourself. This morning as you started stirring from sleep, I heard you over the baby monitor gleefully declaring "Nuh!" "Nuh! Nuh! Nuuuuuh!" with increasing volume and intensity.
I can't help but giggle at the sheer joy you're experiencing since you've discovered 'No', but teaching you the meaning of "Yes" just jumped right to the top of my list of priorities.