You may recognize the work of Paul Klee here. He often used limits in color temperature to create a range of feelings in his paintings.
The cool dominance in this watercolor, for example, sets up the expectation that the mood of quiet will continue.
Night Fire Paul Klee
Here, in a nocturne, Klee makes all the shapes very dark. There is no texture. The thickness of the paint makes it possible for the edges to be soft without the shapes running together. All of the shapes have significant features in common. Perps you're starting to feel like painting....Can you find some shapes, or invent some?
Look up Klee. See if you can identify what holds a painting you like together, then apply those aspects to a painting your own. If you are feeling lost notice that Klee liked to make most of the painting conform to one feature, such as cool dark, while the rest is different in feeling, like the red square, which is relatively warm and light.