Omg do you feel its very dumb of me?

You won't believe till now I used to think Rome is a country and Romania is its other name. Today I found out both are different and Rome is the capital of Italy. I used to always think Milan is the capital of Italy. Today when I found out I was like I am so dumb. A month ago I used to think Denmark is the capital of Greenland but later found out Denmark is a country.