It Never Fails

I try to get stuff done early in one of my classes, and something happens to muck it up. I had an essay due on April 7. I get done with it on March 30 and upload it and THINK I send it to my instructor then. Welp, turns out I didn't send it, and April 7 rolls around and he doesn't have it. He gets it on April 17, which makes it ten days late. One letter grade lowered for every day late. You do the math. I have no way to prove I actually had it done, so I'm basically screwed and have now failed this class. I'm literally sick to my stomach about it. And of course I can't get the instructor to answer any of my emails. Sigh.