Okkkk,
It's probably toe fungus. I know, ick. Easy over the counter remedies, ask your pharmasist what he/she recommends . Try to let your feet get air as much as possible. Good luck. If you have any other questions, I dealt with a fungal toenail infection off and on for years. I may have more ideas for you if this is what you are dealing with.
Good luck
Akso, clean white socks. And if you are intoo homeopathic remedies, I have a great amout of success with tea oil. The real stuff, not same thing you find in bed bath and beyound
mine isnly at the tip of the toenail. also wondering what this signifies