I missed a final exam my first semester of my freshman year. The exam was scheduled for a Saturday morning and since that's usually a day I sleep in on I made sure to try to go to bed early and I set my alarm for the next morning.
The problem is I had trouble going to sleep that night since my hall in my dorm was extremely rowdy. I finally fell asleep at like 12:30, but I woke up to a loud knock at my door at around 3 am and saw two of my friends standing in my doorway. 95% of the time I made sure to have my door locked at night since my hallmates loved to play pranks and mess around, but I didn't this night since my roommate wasn't back when I went to bed and he never brought a key with him.
Anyways, two of my hallmates are standing in my doorway and they ask me if they can borrow a protractor to be funny. I'm half awake and I tell them to leave me alone since I have a test in a few hours. They realized they screwed up, but still asked me for a Gatorade (I had a large stash) and I just gave it to them so they'd shut up and go away. It took me another 20 minutes or so to fall back asleep. I woke up the next morning with 5 minutes till my exam time. For some reason my alarm never went off and because my mental clock got thrown off when I was woken up I wasn't able to rely on my body to wake up on time.
Since it was across campus it would've taken me like 20 minutes to get there and I still had to gather my stuff and get dressed too. I figured at best I'd get there 20 minutes late, which was pretty bad since the tests were a few essays that people usually finished with no time to spare. At best, I'd probably have gotten a C on it because of that. I had no idea what I was going to do.
One of the guys who woke me up saw me in kind of a panic and asked what was up and when I told him my situation he offered to go there with me to explain things. Since I wasn't sure what to do and because an "sick email" sent after the test had already started would've looked like total BS, I decided the best thing I could do was be totally honest about the situation and hope my professor would be a little understanding. Anyways, we get there and my professor seems like he isn't buying the story at all, but he offered to let me take the final at another time with a two letter grade penalty.
I was frustrated because I did everything I could to make sure I would get there on time and some random prank coupled with my alarm not working threw it all off. I realize I was partially at fault too, but without those happening I would have been there no doubt in my mind. I ended up taking the exam and it brought me down from a B+ to a B-. I feel your pain OP, hopefully your professor is understanding.