Problem with lighting
I had a render I was attempting, and one of the figures was not only in a bit more shadow than I wanted, it looked like there was a bit of speckling in that part of the picture. Looking to change things, I clicked on "Create New Distant Light," and hit accept, that's it. Not seeing how or where to place a light source, I simply closed the window.
As you can guess, this is all pretty new to me.
Now the problem is, every scene, in every setting, appears to have had the main light source switched off, and everything is dimmer, everything is heavily shadowed. It looks as if I have created a distant light source, but I cannot find where it is, or how to eliminate it and return things to the original setting. Googling directions hasn't helped, as I find directions like "go to the scene tab, find the new distant light, which will probably be labeled 'distant light 1' and delete it," but there is no light at all in the scene tab.
I don't know exactly what I did, but I can't figure out how to undo it. Can anyone here point me in the right direction?

Comments
Did you perhaps turmn the AutoHeadlamp off (in the Editor tab of Render Settings, under General)? That setting persists until it is chnaged (by you in the pane, or by a preset or scene).