how stressful for you and for you DS.

I really think this is something you need to follow up with the Director. Bribing a child to comply with a comfort item isn't acceptable - whether you're the director or not.

I can understand you wanting to avoid confrontation right now, but perhaps putting together a short email that documents what you understand happened and the effect on your DS would be worthwhile. At the end of the email you could then ask to set up a meeting to discuss it in a couple of weeks time after you've had your procedure. It may also be worth pretending that you weren't aware that it was the Director...

I tend to think that if you let it go for a couple of days, or week or two, it will be much harder to pursue. She may have even forgotten that it happened or at the very least will be sketchy on the details. By making it clear that you're not happy with what took place now you can ensure it will be dealt with appropriately when you are ready to deal with it.

HTH