I was working within my Indesign document and must have accidentally hit a key that turned the background of my document black while also hiding all of my guides and text/images boxes. Any suggestions? Thanks!!
What you see in black is not your document, but a virtual container around your document. Kind of like the table your book sits on top of.
Accidentally you may have hit W which activates this 'Preview' mode. In which case just hit W again and you're back to the initial situation.
Another likely shortcut you may have hit is Shift+W which does the same but in full screen mode.