Presets Showing Up Dark

I have no idea what is going on here, I have been editing for a few hours and all of a sudden I clicked over to a new image and it turned the whole thing dark. Ctrl-Z only deselected the image and then it went back to normal. But when I clicked on another image it happened again. I tried resetting the image and applying my preset (that is not one I have to make big adjustments from) and even when I apply the preset it goes WAY dark. Not sure what is happening or if I've done something to make this happen - hoping someone can help.