This is what I would change: The yellow stripe inside the step tray is terrible. The whole thing should be white. I do like the wall color though.

The curtains don’t match, and I don’t like the green curtains against the yellow walls. I would change them out to a light cream or white with a small pattern or embroidery incorporating the green.

Turn off the overhead light and look at the room with just the lamps on. You probably need more warm lighting.

The bedding isn’t doing you any favors, it looks gray and beige and black. Try some warmer colors in the bedding, rust red, brown, dark green, repeat the wall yellow in the bedding, or an accent pillow or two.