You need to communicate your limits to anyone who you play with and establish safe words. If anyone disregards your signal for slowing down or stopping, that's not a Master, that's an abuser. Just because you are a submissive, doesn't mean you don't get to have hard limits.

Use a form like this one: Hard Limit Questionaire Fill it out and discuss it with anyone before you go into a D/s or M/s relationship.