Actually, Document9 at the task bar. I had opened only 3 new documents
before working on the 4th document. Nothing else before that. This has
never happened before. Once I noticed the problem, I did notice that the
next document was labeled as Document10. Using Word 2002. What did I do
wrong? Where are the other 5 documents that didn't exist to start with?

Everytime you open Word, it creates a new document and counts it, so
even if you didn't save or work on them-you could be at 9.

To restart the count, just reboot your computer.