DS2 is driving my crazy by saying he wants something then when I go to give him it screaming he doesn't. The worst is at nap time. I put him in bed all the while he's shaking me off so he can go on the floor. He's then on the floor and says "want sleep on floor". I say "ok, have a nice sleep", to which he screams "WANT SLEEP IN BED!" to which I say "ok then". "No" he'll say. I then leave the room and hear him run to the door and open it and start crying and shouting "want sleep in bed". I ignore him for a while and eventually I'll go up and say to him to go in his bed. He'll say no!!
Another example today at the park he had his scooter. He didn't want to leave the skate park but there were bigger boys so o said let's go. He was crying and kicking etc so I lifted him and his scooter up and carried him away. I put him down and he wouldn't move. So I started walking away and he said "want go on scooter". I told him to go on it and he said no 
What on earth is this behaviour? I can't make sense of it and it's driving me mad.