When you are upset you are disturbed emotionally to a smaller or larger degree. Being upset does not necessarily have to include the anger component.Originally Posted by Unregistered
According to Cambridge dictionary upset means:to make (someone) worried, unhappy, or angry.
angry...(same dict.) a feeling of fierce annoyance because of something unfair or hurtful that has happened.
a few examples:
I witnessed a horrible accident on my way to work. I was so upset the whole day!
...the accident really shook you up, affected you menatally and it was difficult for you to forget about it.
Notice that there is no "anger" element here. You are not really angry at anybody or anything.
While walking my dog to the park, I saw a young woman being beat up by a tatooed man who took off the minute he saw me. I was so upset.
You were emotionally disturbed to have witnessed a crime but it can also mean you were really angry at that guy.
angry is upset + your reaction to something unfair.