|You didn't say what app you were using, but I don't know if that matters.|
When you say you looked at the "printer box", I assume you mean the dialog box that tells you what documents are printing.
You should be able to highlight the name of the document, Click on the Document menu above it and choose Cancel.
Hopefully that will clear the Print Queue and you'll be able to print. It may take a few seconds to clear the queue, so don't panic.
I hope that helps.