After applying blend mode to every layer, how does one change each slightly without changing others

So I created an indoor art gallery scene that has three walls, in which I laid three seperate paintings on. Each art piece is on a different wall, so they all have different perspectives (z-axis) and thus different lighting. Each painting is on its own layer. I created a blend mode for one of the artworks, which has two drop shadows and one bevel effect to create a 3d canvas look. 

At first I saved this layer style to add to the other two paintings, but I realized I didn't know how to slightly change the style for each without changing the layer style on the other layers. Afterwards getting fed up trying many things, I cleared the layer styles from each layer, deleted my saved layer styles altogether, and tried to apply a seperate blend mode for each layer. But now after creating new blend mode settings on one layer, when I go to the second layer to add a unique blending mode, it still is changing the others. 

What am I doing wrong?