To primer, or not to primer

To primer, or not to primer

My husband and I are in the process of buying our first house. We close on 10/22 and will be moving in shortly after. The room that is going to be my office was previously the bedroom of a young girl. It is painted a pretty lavender color, however it doesn't work for me. Do I need to primer this purple before I paint over it? I want to paint it a light, warm orange color. I've never, ever, painted a room before, so I really don't know where to begin and what is necessary. Thanks for any advice! EDIT: Thank you to everyone for your recommendations. I will prime it, and I will post pics when it's all done. :)
my room :)

my room :)

Kiss my pumpkins, Pumpkin Pervert!

Kiss my pumpkins, Pumpkin Pervert!

It’s spring!

It’s spring!

WALL DECALS

WALL DECALS

new.

new.

Garden in September, caterpillar, mystery plant.

Garden in September, caterpillar, mystery plant.