Arris - I am sure that you know you do not belong in pampers and you know that the people around know that you do not belong in pampers. I am also fairly certain that most of the people who may have observed this scene will understand your mom's anger and embarrassment and - perhaps - poor choice of words.
Verbal and emotional abuse is a real form of abuse and difficult to substantiate with child protective services.
It is important to look at your own behavior during this situation. It appears you do not have any concern for the ketchup that was splattered on people whom you do not know. It appears that because - in your eyes - they were older, it matters even less.
I responded to you on the Moms forum as well. And, again, I hope that you and your mom have put this behind you. I might recommend some family counseling if this is a typical interaction between the two of you. You can also call 1-800-4 A CHILD, the National Child Abuse Hotline for more information on child abuse.
Perhaps, you can volunteer some of your free time to help abused children in your community.