Too much paint

We are redoing Bubs' room with more of a little boy theme. Right now he has puppies which is fine, but we are going to do transportation (trucks, cars, etc.). Although he is so into dinosaurs that I should have done that, but I think the cars will last a long time and he likes those too.

I got the paint yesterday and bought too much. I got 2 gallons of the main color which is fine since he has really high walls (cathedral ceilings) but we are painting color blocks along the middle and putting the adhesive wall stickers in the middle to create a border and break up the blue and make his room really fun and bright. But I ended up buying 1 gallon of each color since I was afraid that I wouldn't have enough with a quart of each. Oops! It might be too much. But even though I don't like yellow that much we might use the yellow to paint the spare bedroom and that would be okay. I was looking at comforters this morning and I'd like to do something really fun and bright in there, but cheap since I'm hoping to have another kid within a year or two.