DD, 2.9 is going through a defiant phase at the moment. As part of this, she is saying "no" to everything, even things she wants to do.
This morning, DH offered to take DD to the library (normally a favourite activity) before he goes to work later, so I can catch up on some jobs at home. DH asks DD to come. She says no. I make it clear that I will not have time to play for the next hour. DH leaves, she screams "I want to!". I encourage her to get shoes on and chase DH down the street, and tell him she now wants to come. She does. He then encourages her to get in the car. She says "no". I tell her that I will count to three, and if she doesn't go, she will come back home, as DH needs to get off to work afterwards. She doesn't get in the car. I take her home. She is now wailing "I want to go!" and is showing no signs of stopping . I am continuing with the chores, and have said that I will play when I'm done.
Sounds fair enough if you haven't got lots and lots of chores. If it's going to take longer than 10 mins or so maybe change tack to "I will play when you've calmed down"? They can't wait very long at this age, I seem to recall.
Sounds fair enough to me, you gave her every chance to change her mind. But I bet there's some complicated brain/language development thing going on that explains why they say no all the time at that age even when they want to do whatever it is, i.e. she's not being a pain in the bum entirely deliberately.
i discovered this trick once upon a time when my brother was a toddler and i a teenager i.e. before i had kids and lost the ability to do anything creative the TRICK has since worked wonders with my own childen. note - it may be interpreted as allowing your offspring the intelligence of a sea urchin and it heavily relies on your acting skills BUT worth a try
instructions: rather than saying "let's dress you!" you get into character and pretend you don;t want to dress her. you obviously have to verbalise this and it's even better if another adult joins in. the hard bit is that you have to stay true to your normal self so the little rascals don;t get the idea that it is a game.
once mastered this works wonders for a toddlers biggest pleasure lies in doing the opposite of what you want.