I think you were smart to listen to your gut. Your instinct to protect yourself until you know the Dominant better is the right one. There is a time and a place to lower your boundaries--after only a short time of interaction, this wasn't it.

If the Dom/me will not respect your 'no' in a non-sexual discussion in a public forum, how will you be able to trust that they will respect your hard limits when you are bound and gagged?