How can I recover deleted/replaced texts even after saving the document?

I wrote an essay in another language and soon after finishing the entire write-up, I saved the document and exited the file. When I came back, I was pretty much greeted with a heck load of question marks in replacement of the text that I wrote. Is there any way I can recover the text within the file now?
p.s. I saved it in docx, if that’s of any significance.

Never use foreign file formats for ongoing work, especially DOCX/XLSX/PPTX. Work with ODF and only after finishing export to another format. In your case, I am afraid, there is no chance to recover something (unless, of course, it is a mere font issue).