hi
i reckon go see a doctor, tell them about your SA, hopefully he'll be able to give you something that will help
go see a psychiatrist/psycologist (whats the difference?) aswell
a doctor was the first person i told about my SA, (i sat there talking to him and i was going red and sweating, thinking the whole time i was looking stupid and humiliating myself) but over the proceeding few months he had me try first a beta blocker? which is called Atenolol, it stops the adrenil glands from producing adrenalin or something to that effect, it works great for keeping your heartrate slow because when you get paniky it is a fear reaction and adrenalin will be pumping through your veins reading your body to "fight or flight" this doesn't stop the sweating though, but atleast you'll feel alot calmer and maybe even not sweat so much because you will feel calmer and hopefully you won't feel paniky at all, but these seem pretty safe and the effects only last maybe an hour or two- apparantly musicains use them before going on stage to keep there heart rate normal and to stop shaky hands and stuff like that.
The second thing the doctor put me on was an antidepresannt, called aropax, but this takes many weeks to kick in and maybe it made me more chatty but i didn't really like it that much because at time i felt lightheaded + there are other side effects. So for your presentation this one isn't an option.
But definitely talk to your doctor, and then get onto a psycologist for further more comprehensive help. I recomend a Cognitive Behaviour Therapy, its definitely working for me, i used to be pretty much just like u , i haven't had a panic attack in quite a few months and i get red and sweaty way less.
good luck
