My tongue has been sore for the past couple of days. I have little red spots on it that came with the pain. I'm also diabetic and have metal allergies?

Allergic reaction? Sounds like you came into contact with some type of allergen that your body is not happy with. I would try to recall what types of foods, beverages and smells you came into contact with in the last 24-48 hours. Take that information with you to your doctor so they can help identify the exact cause and help reduce future chances of a problem.
See below. Have you done or eaten anything different the past few days? This sounds like an allergic reaction or an irritation...If this doesn't go away in the next few days i would go to the dentist and let them take a look at you.