Glad you still were able to eat the pizza Always wear an oven glove to protect your hands when near the oven. Oven burns really hurt.
One thing you should always do after a burn is run it under cold water for 10 minutes or more. You need to tell your parents or an adult, since burns can be serious. In most cases they will just get better on their own, but you need to have an adult look at it to to be safe. If it is really bad, like you get blisters, or the skin is very red, you might need to have a doctor look at it.