5 Days Post-Op Rhinoplasty I have Inflamed Red Throat, is this Postnasal Drip?

You may be right that your sore throat was caused by suctioning. Also if you had a breathing tube inserted during your procedure, this can irritate the back of the throat,eg.LMA. Also because nose is stuffy, you may be a mouth breather for a while This can dry out the mouth and cause throat pain. Hydrate and use topical membrane analgesics.

It could be all of the above.  It could have been from the tube, from post-nasal drip, or even strep throat. You may want to get this checked out.

Your sore throat after rhinoplasty is likely due to your anesthesia, not nasal drip, and should clear up after several days. Throat lozenges will help you feel better.
Best of luck, peterejohnsonmd.com

Your throat may have been irritated from a breathing tube used in surgery. However, the best thing to do is ask your surgeon to take a look.

A sore throat after rhinoplasty is not uncommon. You may be able only to breath through your mouth because of internal swelling. Also, if you weree intubated some discomfort will often result

All of your  theories are possible explanations of your sore, inflamed throat but I think your discomfort is most likely secondary to the anesthesia tube. Your symptoms will  continue to improve; throat lozenges and saline gargles will help. Consult with your surgeon.