That's definitely an unfortunate experience, but isn't giving presentations to explain your ideas - sometimes to people you don't really know - actually a significant part of the job? I'm an IC, and I present designs and project plans for feedback to groups of up to a couple dozen people, or to VPs, on a pretty regular basis. If I couldn't do that competently I would be failing at my job, because that kind of communication is just as important as actually writing the code. If I were conducting an interview and discovered that "public" speaking on the order of a few people in a conference room was extremely difficult for you, I'd probably consider that an important red flag.