Hello, My Name Is Becky And I Am Having An

Hello, My name is Becky and I am having an issue with my toe! I do suffer from Numbness in my feet that is not associated with diabetes. One of my toes has a history of having hardened skin on the top of the toe. I have recently noticed that this area has become much darker...I would even say black. It this cause for a medical emergency?

Thank You,
Becky Deininger
YYYY@YYYY