Right Foot Recently Became Painful After Fairly Short Periods Of

Right foot recently became painful after fairly short periods of walking.
Yesterday, a sharp shooting pain on the side of my foot would last for a few seconds, then stop, and recur at short intervals. A crescent-shaped red rash appears in the area of the pain, and a very small break in the skin. I have mild type 2 diabetes and have noticed in the past some lost of feeling in the feet, especially the right foot now affected by pain.
Not especially responsive to aceteminophen or ibuprofen. What should I do?