I get this. I've been there many times before! I would probably have rather died than speak publicly...however , I worked through it via cognitive behavioral therapy and by practicing relaxation techniques. I also had to speak in front of people A LOT before I was somewhat comfortable doing so! Now I occasionally get nervous, but not with the same gripping panic as before...just some slight nervousness.

It was mostly likely a panic attack you experienced...as someone stated before, we each have our own different version. I can relate to the feeling of near-fainting, along with my voice sounding like an 'echo' (extremely far away!)

Try some deep-breathing and stress reduction techniques (you can find many online) that you can equip yourself with and use when the moment arises again.
Best wishes.