Many indications of diabetes occur first in the feet. Familiar diabetic foot problems include infection, nail fungus, neuropathy, poor circulation, ulcers and foot deformities. Loss of feeling, pain, coldness, blisters or sores, numbness may be signs that your diabetes is out of hand. Patients with diabetes who get bunions, calluses and corns have an increased risk for getting foot ulcers; aka open sores. As well as wounds that heal slowly or lead to infection.