I fully agree on this with jeanne.
About "this community not being the right one" - Iīd be cautious regarding that.
chalsia - I donīt know if itīs any help, but with the scene people hubby and I know, the birthday spanking thing is something special - the sub gets her birthday spanking by everyone in the room, no matter if those other persons are Dom or sub.
Itīs actually a sign of trust to be asked to spank the sub in question.
There is nothing more behind it - you are not asked to switch or to Domme, you are just asked to spank at this one time :-)
Nobody will expect you to make a convincing scene of it, or will ask you to switch on other occasions - if things are there as they are here.
Everybody we know in r/l knows perfectly well I donīt have any dominant streak and do not want to switch, but even I have been asked to give birthday spanks, and I have to admit it was rather funny :-)
I would not worry overmuch, just go back and explain. It is perfectly okay not to do something/ not to want something. Saying so politely instead of running away would have been perfectly ok.
Keep in mind that even BDSM people are simply people - nothing more, nothing less.
If, however, they expect you to act in a way that makes you feel uncomfortable, avoid that crowd in the future.
But I really donīt think that is the case.