Help! is it possible to have diabetic foot without being diagnosed with diabetes?

No: So we need to know what you mean by "diabetic foot." Do you mean neuropathy? The tingling, burning, or loss of sensation? Or do you have open sores on your feet?

Yes of course: If you have not been to a doctor in years, it is possible that you have come down with diabetes and now have foot problems. I have to diagnose diabetes in my eye clinic every week. If you have seen your doctor and had diabetes ruled out, then no, you can't have a diabetic foot. The only exception I have seen is a longstanding case of diabetes with problems now reversed through diet and exercise.