The EASIEST way to accomplish what you need now would be to export a PDF from this document as single pages and then create a new 5.5x8.5 document with facing page and then place the PDF into the new document.
To make it easier you can use the place multipage PDF script. Once that’s done, just export a new PDF and you should be good to go.
Unfortunately, the print shop boys are right and you made your document wrong. There is no need to "manually" create spreads, InDesign is perfectly okay with providing you with these *if necessary*. And that's a courtesy, because it's almost *never* necessary.
Turning your document around is not going to be an automated job. So indeed,
>.. this is going to be quite time consuming, thanks!.
Fortunately, you Learned an Important Lesson here, so it was not a total waste of your time!
Also, this set up was the most helpful for sharing this as a PDF for others to read straight through.
You can easily create reader spreads from a PDF made of single pages by using Acrobat's property for Initial View > Page Layout > Two-Up (Cover Page)
The "print shop boys" might or might have not something that can turn your false spreads into good pages, but basically it's your responsibility to provide pages and no spreads. Let them do it and for a fee, if they provide that service…
There is special software like the Callas "pdfToolbox 5" that could perform this task. If you like to, google for it and use a 30-days trial. But I bet, you will need more than a few hours or even days to find out all the dos and don'ts of professional PDF creation…
Oh. Could be, that this all would not work, because for "spiral bound" you will need bleed on every edge of the page. That depends on your actual page contents, especially if objects will cross the spine. Better ask the print shop how to provide that and how much bleed they want…