Jenni,
One thing that has impressed me from the first time you posted, and thereafter, is your honest curiosity and genuine feedback. You are a refreshing member of this site. I don’t think you need to worry about coming across as unkind because it is evident that you have no bad motives.
Just a note on the people of the United States being called Americans, I think it comes from the fact that their/your country is the United States of America. They’ve simply taken the last word in the name of their country to identify their citizens, I don’t see any problem with it. We all have a way to identify our country of citizenship. I’ve never thought that it implied a monopoly on North America. Carry on Americans! You have a great country, we have adopted two children from there and we are blessed to have them!