My sister embarred me & I'm pretty angry?

Oh how I know what you are feeling. I however do not have the self control you seem to have. What she said is really not that bad. Hanging on to the anger will only hurt you since your sister does not care. She will in time come to realize how childish she is behaving and hopefully change for the better but until then you should not let her rude actions affect you. It will add stress to your life that is not needed. Do something like go for a run, listen to music, or beat the heck out of a pillow to release the stress and let it go. It is the best thing to do since you have already confronted her and she does not care.