Layer merging doesn't work

I have 3 layers.

The first is at the top. It's a radial gradient which is set to the layer blending mode "Color".

The second is in the middle. It is a black and white difference cloud layer that is set to overlay.

At the bottom is my third layer. It is supposed to be a bunch of stars. By stars, I mean a noise filter applied to a black canvas.

The problem is that if I "blend visible" or "blend down", it looks nothing like what it showed me when i turned on the visibility on on all of the layers. It also looks completely different when i zoom in.

create a new layer on top
and hit

CTRL SHIFT ALT E

great thanks. I was having the same problem