The Olympic gold medalist, 20, had been expected to present an award alongside the rest of the Final Five but, before the show, revealed on Instagram that she was "out of the hospital & resting comfortably."
On Tuesday night, she gave a longer explanation for what had happened, posting an Instagram of her at the dentist's office.
"Hey guys! Just wanted to let you know that I'm doing ok! I had a complication from a prior injury that caused a cyst to grow on a bone in my mouth. Got it removed and feeling much better now," she captioned the picture. "Thanks for all your concerns and prayers and HUGE thank you to the doctors that have taken care of me these last four days!"
Though she's on the mend, Douglas hinted that there may be more surgery in her future. She closed her message with the hashtag "butIstillgottagetthesewisdomteethout."