People As A Trigger

Sounds weird, right?  It's true though.  Sometimes just the presence of people can be enough to be a serious trigger.  It's something I badly struggle with and I know I am not alone and its something which needs more awareness.  They don't need to speak to me or even look at me, just their presence is enough to freak me out and feel trapped and when I feel trapped I do a runner.  Tomorrow I have to face my worst nightmare.  60 more strangers joining an already crowded and noisy room.  Just the idea of it scares the shit out of me and gets me worked up.  As always I will try but a word of warning to anyone in a mile radius of town centre tomorrow, there will be a panic attack at some point.