Car is in color!!!!!!!!!!!!!
If you plan on re spraying I would buy some 600 grit DA paper, DA the entire car then wet sand with some 800 and a hard block, Thats the quickest way. Otherwise start blocking the car.
Its probably best to buy all your paint at the same time so the same guy mixes it. The difference could also just be because one is single stage and the other is base-clear.