I got braces yesterday evening, and I can't talk right.?

I just got braces yesterday, and I can't talk properly. I sort of have a lisp and I am slurring my words. Tommorow I have a long important speech to make. Will this go away? Or will I be like this until I get my braces off? Oh. Also, when I talk I don't know how to form my mouth anymore, since I got them. Thanks!