Layer styles alter the entire layer.
If you do not want layer styles applied while painting, paint on a new layer without any layer styles applied to the layer.
Layers have internal structures. When you create an element such as type, a shape, vector object, or a brush stroke you start at the level closes to the canvas. Lets call this the painting area. When you add a Layer Style it gets stacked on top of or below the painting area in a predetermined location. The order in which the layer styles are listed in the Layer Style dialog refers to the order they are stacked on top of one another.
The structure of layers with layer styles is somewhat complex and can be difficult to grasp unless you study it a bit.
Some Layer Styles will always fall below the painting area, while other Layer Styles will always be *above** the painting area. There is no way to add pixel data above some live layer styles on a single layer. With some Layer Styles you are always painting underneath the layer style. You can not change the stacking order of live Layer Styles.
The "Overlay" Layer Styles are designed to cover all pixel data on the painting level. Therefore, you can't use an overlay layer style and ask it to ignore a portion of the painting level. It sees the entire level. The exception is a Pattern or Gradient Overly which contains transparency, or any Layer Style where opacity has been reduced.
If you need different colored pixel data which is not effected by the layer styles, you need to add a new layer. The structure you are seeking is simply not possible on a single layer.
An alternative, which may or may not work for your given circumstance, is to right-click (Windows) or Control-click (Macintosh) on the Layer Style icon to the right of the layer name in the Layers Panel and choose "Create Layers":
This will split the layer styles into raster layers and their stacking order can then be altered. But be aware, this removed the dynamic ability to alter the Layer Styles any further. When you
Create layers you are doing just that and each layer is then a standard pixel-based layer.