I just wanted to add a few points that I hope help you out.
I too experienced intense anxiety similiar to how you describe in high school for presentations and speech class, as I also suffer from social anxiety. But at that time was too shy to raise the problem to anyone so never received medication and had to bear the brunt of it.
Wanted to say first of all, when I went through college, we had the option to take CLEP or Dantes tests to get out of these classes. I did a Dantes test for speech, which involved going alone into a room with a tape recorder, getting 10 minutes of prep time and recording a short speech. This worked for me, and if you inquire or raise the issue to your councelor maybe they can take it further.
I wanted to also say there is hope for even the anxious of us all. After I entered the workforce, I was sometimes required to give presentations for interviews, clients, and even teach a class of people way smarter than I am. What worked for me is that I found if I have time to prepare material and become familiar with it, I am much more comfortable because I have a script to stick to. And, if powerpoint presentations are an option, focusing on those while presenting helped alot.
Over time I have become much better at presenting (I still dont think anyone becomes 100% comfortable), but I do not get strong anxiety. I will admit that sometimes I will take .25mg of xanax, just enough to help, or maybe its a placebo, but for the most part the anxiety is not a major issue anymore.
While the pills help, they are a temporary fix. What I found to be a permanent help was being thrown into strong situations and facing them head on. While it can be a huge battle going through it, I found my confidence skyrocketed after I did make it through something. I always found that when I played the scenarios and possible outcomes over and over in my head, this fueled my anxiety. If I instead prepare and focus on the material for the speech, I found that once I got up there I was not as nervous as I had imagined.
In a class, it takes time, because instead of one big presentation you have them spread out into smaller speeches over time. But, think of it this way. The first speech you did on day 1, where you gave a brief intro about yourself, had to be winged because you had no time to prepare. In that sense, the hardest is over. For the rest of the speeches, such as when you interview someone else, you can take notes and have material to prepare with and focus on.
In summary, I promise there is hope and that this may not be a lifelong situation. Going through a speech/presentation is a huge internal battle for someone like us. But, like I said, focusing exlcusively on the material to be presented, and knowing it well, always gave me a "Crutch" in the presentation, because I knew no matter how flustered I got, I would have the material to fall back on. When I had this, the anxiety would build from the moment I knew I had to give the speech until a few minutes before I had to give it. But, when I actually walked up and began to give the speech, looked out at the crowd, I realized that I wasnt nearly as nervous as I thought I would be, and I had played a lot of it up in my head. It is still a tough battle, but if you can make it through a couple, perhaps even mimimally medicated or not at all, your confidence will grow and anxiety will be reduced for later situations.
Hope this helps.