I've made a huge mistake

A couple of weekends ago, I went out for my first run in quite a while. The goal was three miles- something that was rather easy for me say, last October. The first half mile, I tried to chase the thought that most people "walk" more briskly than I "run" from my mind. I coached myself with the thought that if I've done something before, of course I can do it again but as I slowed to a walking pace for thirty seconds of recovery after two miles, I remembered that one time doing the paper route with Ben at two am and listening to that weird trance station on Sirius and saying "Voooooortehhhhhx" in the most monstrously deep, cavernous monster voice I've ever produced. Ben and I looked at each other, our eyes enormous with astonishment. I tried to replicate it. Hundreds of times I've tried. Mostly with earnest eyes eager for Ben’s approval. Each time he just shakes his head.

I came home, chugged a couple glasses of water, drank a glass of wine and registered for a marathon. Since that moment, enormous doubt has set in.

Last night in class for some reason I drank a Dr. Pepper. While eating half (okay 7/8s of) a bag of sweet and spicy chili Doritos. I… reeeeally… don’t know why. I came home and briskly changed into running gear before I could talk myself out of it. Half a mile in, I thought I would surely die. I mollified myself with the proposal that considering I had consumed about a pound and a half of ASTHMA, the two miles I managed to eek out were more like four.

Today at work, I started stressing about the marathon and decided to look up some (propaganda) inspirational information online. I googled “normal people running marathons”. Below are some quotes I came across.

Hal Higdon, running writer and coach:"The difference between the mile and the marathon is the difference between burning your fingers with a match and being slowly roasted over hot coals."

Jacqueline Gareau, 1980 Boston Marathon champ:"The body does not want you to do this." (okay, the rest of the quote gets a little more inspirational, but...)

Rob de Castella, winner 1983 World Marathon Championships:"If you feel bad at 10 miles, you're in trouble..." (again, this one gets a little more inspirational, but...)
Bill Rodgers, winner of four Boston and four NYC marathons:"The marathon can humble you."
But, walking up stairs humbles me. Actually, so does walking down....
All of these were labeled “motivational”.

Then I found this article:
Marathon Deaths Spark QuestionsWhich starts with the line “Last weekend, three runners died during a half-marathon in Detroit. All three were reported to be healthy, and two of them were young.”
Which leaves me in a quandary...
Why would someone who would forego a four dollar massage because she doesn't want to spend the money pay ONE HUNDRED DOLLARS to be slowly roasted over coals and possibly die?