Original Brush Stroke on Left / Adjusted Image on Right.

If this is the effect that you want then these are the steps I took:

1. Create a new layer and put your blood splatter brush strokes onto it.
2. Go to Filter>Stylize>Emboss - My settings were Angle 144/ Height 25/ Amount 50.  Adjusting the angle allows you to match the light direction of your blood splatter to that in your image.
3. Add the following adjustment layers: Colour Balance, Curves, Brightness/Contrast, Hue/Saturation and create a clipping mask for each adjustment layer (Layer>Create Clipping Mask) 
4. Adjusting the red channel in Colour Balance brings the embossed image back to blood red.  Curves and Brightness/Contrast adjust the balance between the light and dark areas of your blood splatter.  Adjusting the saturation and the lightness/darkness of the red channel fine tunes the blood colour.

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