Only one layer working?

Hello,

I am working with a sequence of jpgs, each in their own layer. I have be isolating parts of the indviduals images in their layers and going down the sequence, however now only one of the layers is woking. That is, only one layer and image is visible, even when layers above are on. When I try hiding the layer, the layers below don't show although they are on. It seems to be a random layer in the sequence, but only that image is visible. When this layer is off, all I get is the transparent packground.

When I try to export any other one of my layers it says there is no selection. 

Does anyone know why this could happen? or did my Photoshop just crash and I have to restart?