Are you sure this is a result of just toast? Are you sure they are just on your tongue?

You could be "roughing up" your mouth with coarser foods, but something like toast wouldn't cause you to have red bumps, but it might just feel a little sore or scraped, and it would be sore on the roof of your mouth as well. But it also could be aggravating a condition that you already have.

Vitamin A, C, E K, and the B complex is good for the skin. You can try that, but if it doesn't get any better, maybe you have some sort of infection or allergy to the food that you are eating.

You should go to a doctor and have yourself checked out and tested for a bacterial infection.