What Causes A Tender Bump On The Foot Above The Vein?

Thank you. There is a vein at the top of my foot (the top about where I tie my shoes) there is like a bump that is very tender and at times radiates down thru my top of my foot to my toes. The bump is not large (dime size) and it feels like a volt of electricity goes thru it when touched and interferes with my shoes, walking, etc. The bump is kind of hard and seems to be in the vein. Should I be concerned?