Should I have said something to sitter?

So today was my 9 mo. old's first day at the sitter. When I went to pick him up this afternoon she said he was good until he got sleepy then he started whining so she rummaged through the diaper bag and got out his pacifier, gave it to him and he took a nap. She handed me the pacifier she gave him when we got ready to leave and there was only one problem: it wasn't my sons pacifier! I said 'Is this the pacifier you gave him?' And she said 'Yes, is that okay? It was in his bag.' I just smiled and stuck the pacifier in the bag. I know accidents happen esp. when 4 little ones are present so I didn't want to say anything plus it was my sons first day and I could tell he enjoyed it there. So should I have said something? Would you have?