Well, everybody has his worst stuttering experience, yours was just today (i had something similar like you when I was 16. I think I cried and stuttered my whole presentation, probably everybody forgot it by now). Not a big deal. You will get over it, with time. In one week you will feel better than now. Dont think much about it. And as always, try to find a good speech therapy ;) So you dont need to deal with this shit anymore.