While many conditions are self-limiting and improve with simple home remedies, your rash seems to be causing you enough discomfort that seeing a doctor would be appropriate. Severe rashes that do not respond to over the counter treatments need to be evaluated by a physician. You state that the itch is "unbearable" and that you are scratching to the point of bleeding, those word imply that you need professional medical care. Scabs and sores on your feet may limit your mobility and make you prone to infection. If you are a diabetic it is especially important that you see a doctor.
If money to pay a doctor is an issue, you still have some options. Many cities have free or low cost health clinics where care is billed according to what you can pay.