Adding layer mask changes my brush color.

[FleXz23323185eqaf]

I wanted to add a layer mask above my painting but it keeps changing the color, please help!

[D Fosse]

That's not a layer mask. That's a normal pixel layer clipped to the underlying pixel layer.

Add a layer mask by clicking the mask icon in the Layers panel. It will appear as an additional thumbnail beside the pixel thumbnail. A mask is always black and white. Black areas hide the pixel content, white reveals.

Here's how layer masks look:

[FleXz23323185eqaf]

I'm sorry but i think i confused "Layer Mask", with "Clip Mask Layer" i don't want a Layer mask i want a clip masl layer above my painting so i can only paint over a certain area and not the background. But whener i add it my colors will change.  

[c.pfaffenbichler]

The appearance of the top Layer in a Clipping Mask Group obviously depends on the base Layer. 

So what are the base Layer’s Opacity, Fill, Transparency of the actual pixels, …? 

According to your screenshot it is semi-transparent, so the result would seem to be as expected. 

[D Fosse]

That's right. The underlying layer is transparent, so this is all as it should be.