Master bed room paint color

We picked a paint!!
Behr's Sculptor Clay.

I am going to paint the whole room this color with the chair rail in cream/white. I do have a slight problem with the color...
Can you see anything off in these pictures??

To me it looks like the paint is different when on top of the brown paint vs. on the white paint. Both squares have two coats of paint. I really like the lower paint swatch, but not the top one. Do I need to prime the brown? I think yes. GAH thinks it is just an optical illusion and priming the room would just be extra work.
What do you think??

The window in the pictures is going to have these red/cranberry linen curtains. I think it will look very nice!
-ELH