Black Toenail

Hello!

I stubbed my toe yesterday and after my long run today I noticed my toenail was black and there was a bit of pain. Currently training for a marathon with a peak week next week, and I was wondering if there’s anything I can do to alieviate the pain and cause it to turn back to a normal color. Currently wearing shoes that were chosen for me after a fleet feet foot analysis, and I never had any issues with it until today. I know this also probably varies per person, and hopefully this isn’t a dumb question, but do you know how long it takes to recover from this? And if I do lose a toenail, is that painful? How long does it take to grow back? And most importantly, anything I can do to prevent losing a toenail?

Thanks,
A runner who would really like to get to the start line with all 10 toenails :)