I'm sure you didn't use your safeword lightly...and even if it might seem that way looking back with the knowledge you have now (that he was only messing with your mind) - at that point you felt things were overwhelming. To me, that's what counts - not what makes sense now.

I think you did the right thing in letting your dom know about how you felt and raising the stop sign...please don't feel bad about it and talk, talk, talk with your dom! *hugs*