I cannot convert my Microsoft Word to pdf file

I'm a writer. I created G.I. JOE and TRANSFOPRMERS, and I have converted WORD files to it pdf without incident many many times. I tried . I this instande, I had done it, I thought, but the page on screen turned gray, and nothing I evoked a reaxction.  and then the copy box stared flashing inremittently, seemingly going nowhere so I left and got back to my emial to deal wioth a contract coming in.  hen I booted up again, my desk top screen was filled with pdfs of sections of my novel of various lengths filling the entire  screen. WHAT THE HELL HAPPENED AND WHAT DO I DO ABOUT IT? I still have rhe original WORD version buyt it is terrifying