When I was young I used to have a pain in my ankle and then it went away and just a month ago I was playing football and I jumped on to someone and my leg and ankle bent back I think and then the pain came again, whenever I walk up or down the stairs or when I lean my leg forward while keeping my foot in the same place I feel a slight pain in the upper front of my ankle but whenever I put my ankle in a normal position I don't feel the pain, Please help thanks.

Chances are that you've sprained or torn the ligaments in your ankle. You should see your doctor, or the team doctor/sports medicine practitioner, about this and get it treated.