Foundering

It's not the first time, and I always knew in my mind that there would be a second time, so I don't know why I feel surprised. Still, after my run last weekend I was not feeling any discomfort and could see no discoloration (not that I thought to look for any, since there was no discomfort).

But now I look at the toenail on my right big toe and the bottom left quadrant is purple. It started on Tuesday as a faintly different shade of the normal pinkish-purplish that my toe nails normally are. And in the days since it has grown into a more robust shade of purple with more clearly demarcated edges. And it appears to be getting bigger.

Science has two theories while runner's toe nails come off. Both are linked to nails which are longer than they should be.
Theory #1 says that the edge of the nail gets caught on the sock or the shoe or something and gets pulled upwards as the foot rolls through from heel to toe, with the most pulling force being applied at the point of push-off. The pulling causes a small separation of the toenail from the nail bed which leads to the nail falling off.
Theory #2 (I like this better) says that the nail is being pushed back onto the toe over and over and over with pounding force, and that this separates a portion of the toe nail from the nail bed (does not need to be any particular part of the nail) which leads to the nail falling off.

In my defense I trimmed my nails the day before the race, so this should not have happened to me.

I 've tried ice and rest, and now I'm going to have to run on it anyway even if it does hurt. I'd like the nail to stay on, but I know falling off is not the end of the world if it does not.