panic attacks

I have really bad panic attacks and especially speaking in front of my classes or in front of a huge crowd. So, for me I try to avoid it at all costs, but today I got a call where teachers have chosen me to speak in front of my whole school since I'm doing an organization with friends but it was my idea so I've been chosen to speak. Now for me this is a huge deal, I kid you not I've been stressing so much that I physically can't breathe. My hands get really sweaty every time I think about it and my hand shakes even more than they usually do. I'm so scared and I get anxiety attacks as well and ngl I think I'm having one right now, I don't know what to do. I have to talk next week and I just wanna cry.