I'm so sorry that you have terrible public speaking fears. I have the same, albeit not as intense as your particular situation. When we have to introduce ourselves to the class, my heart starts pounding so hard I swear the person next to me could hear it! I also have to do a ten minute presentation for the end of the quarter, and I am sure I more fearful about it than anyone else. To make matters worse, I am in a grad school where all of my peers are better spoken, more mature, and older than me.

A few advice I can give you to help you through your journey as it has helped me:
- Don't suppress your feeling. Don't try to wish the feeling will go away. It wont. In fact, it will get worse because you're ignoring a message that it's trying to tell you. For me, that message was that I was unsupported and unvalued. I had no one to talk to about my insecurities. Instead, I was constantly under the scrutiny or others and no one gave me kind words. Because no one said that "me" was good enough. I decided to seek support after that message, and it has been helpful. The support is online, but some support is better than none.
- Journal about it. Let your thoughts run wild and let it all go. You'd be amazed how much better you'll feel after saying your emotions out loud, and maybe even after a good cry.
- Don't believe that you're the only person that is nervous about public speaking. Most people freak out about presentations and interviews and related things. They're just holding it in, just like you are. The nervousness intensity just varies from person to person.
- Practice your presentation over and over and over and over again! Record yourself. Do it in front of a mirror. Have it done so many times that you know the presentation like the back of your hand. Do it until you are absolutely and totally comfortable presenting it alone. Preparation will alleviate a good proportion of your worries about not knowing what to say during the actual presentation day.
- Take deep breaths. Make sure your belly rises as you inhale.
- Do a "superman" pose or extend your limbs out for several minutes before you begin your talk (privately, like in the hallways or bathroom). Studies have shown that the "winning" pose (the pose you often see others make when they win, such as a runner being the first across the finish line) lowers cortisol stress hormone levels and boosts confidence. Never shrink your body up and make yourself appear smaller. That pose raises cortisol.
- If your body wont calm itself down no matter what you do, test out propanolol. Ask for a prescription from your doctor - it will drop your blood pressure, undo the shaking, and prevent you from having a heart attack. Test it out before your presentation, such as a moderately-stressful event, to see how it works on you.
- Help someone else out! When there is SO much attention on yourself, you feel extra alert and stressed out. So reach out to someone else that is suffering and relieve them of their suffering. When you made someone else happier, you become happier yourself.

Don't avoid stressful social situations. Embrace it. Force yourself to participate in class; raise a hand and ask a question or make a comment. If you do it enough times, you will eventually get desensitized to it and your performance will improve. Nothing lasts forever, and this event of yours will become your past soon.