I'm losing my voice and I NEED to give a speech?

On Thursday my sinuses were draining, on Friday my throat was sore, and today my voice is scratchy and fading. The worst part is that on Monday I have to give me Valedictorian speech at my graduation. I sort of would like my voice for that. I'm drinking green tea, taking allergy medicine, gargling salt water, taking dayquil and nightquil, and flushing my sinuses with salt water. Do you think I'll get my voice back by Monday? I really need it. Any advice or tips would be appreciated.