I have been trying to create adjustment layers but my photoshop just doesnt respond normally. When I click on adjustments > curve, I should be getting a new layer linked to the curve icon in my layers box. But all I get is the curve icon, I can't modify this "layer" coz I get a message saying this layer can't be edited because it's empty (applies to any kind of adjustment). Here's a screen cap, hope you can help me with this, million thanks !!!

