Frozen in the Face of Terror

This might sound weird but I don't get nervous speaking in front of people.  I've given a ton of presentations.  I've taught classes, I've given presentation to high school students trying to get them to like engineering, and I've talked so much about engineering to my professors I get bored thinking about it.  I've even presented engineering work to non-engineers.  All those times I get a little nervous right before but that's it.  Well not this time.  I'm talking at a conference next week and preparing the presentation right now.  I wasn't nervous until I made the presentation.  Now I'm absolutely petrified.  I have to practice the presentation tomorrow in front of my professor and truly that is what scaring me the most.  I don't know why but make a fool of myself in front of this person is more terrifying than presenting in front of professional engineers.  But then again I haven't gotten to that part yet :).  Right now I'm just paralyzed.  Ugh.  Fear.  It's a terrible emotion.