Color Replacement

Replacing a color in Photoshop is different from replacing a color in Illustrator, and there are even different ways to replace color within Photoshop based on how your file is set up.

I'm wondering if your brush has transparency applied. That would make some of it lighter.

It would help if you could share a screenshot that includes the canvas and the Layers panel.

Here's how you could change the color with the Hue/Saturation adjustment layer:

1. Select the layer with your brush strokes
2. Go to Layer > New Adjustment Layer > Hue/Saturation... and click to let OK for the autonamed layer (or just click the Create new fill or adjustment layer icon at the bottom of the Layers panel (it's the middle one that looks like a black and white cookie)
3. Click the Properties icon in the Layers panel to select the Hue/Saturation properties, and go to the Properties panel (Window > Properties)
4. Click the Colorize button near the bottom of the Properties panel
5. Drag the Hue slider to the color that you want.

If your brush strokes are on a background layer filled with white, you may need to increase the lightness on the slider in the Hue/Saturation properties.

If you used a specific color, you can click on the finger with the arrows under Presets, select the color on the canvas with your cursor which will change into an eyedropper, make sure Colorize is selected, and then adjust the Hue slider.

You can also use the Saturation slider in the Properties panel to further refine the color.