Miscommunication... I loathe you.

It's been about 11 months since I arrived in Japan and I have yet to master this language. Mastering this language is some feat, though the regular Sunday classes are indeed helping. Personally, I feel I have somewhat of a basic grasp of the language, enough to carry a simple conversation or listen in on the new gossip in the teachers' room at school.
This, however, is about miscommunication. I'm sure I won't go a day without being misunderstood or without having some kind of language barrier.
"I said, I would NOT like a plastic bag with that food which is already covered in 3 layers of plastic".
But this one tops it all off. I was at the gym yesterday wearing my "Queen's University" T-shirt, you know, the gray one. A young guy working at the gym struck up a conversation with me, in Japanese about my shirt. Explaining to him I went to Queen's and the meaning of the name, he was intrigued that the head of State was the Queen of England. Through much explanation I tried to convey Canada as Constitutional Government with a bicameral legislature.
Both Japan and Canada have a prime minister as the head of legislature, and a monarch, the Queen of England and Emperor Akihito respectively. As you may, or may not know, the current prime minister in Japan is Taro Aso (referred to as Aso-san... people are called by their last name, followed by "san" as a sign of respect). Anyhow, I mentioned Aso-san to compare Japan with Canada's bicameral system, though I didn't think I could mispronounce Aso-san.
I managed to instead refer to the prime minister of Japan as Aso-san (a mountain in Kumamoto, Japan). I didn't extend my "o" at the end of Aso. It took me a while to realize I had confused my friend and that we had a misunderstanding.
Share your thoughts.

Communication is key!
PS: One thing I learned yesterday. The word for expert in Japanese is "Jouzu" which is made up of two Kanji... up and hand. Wanna know the etymology of the phrase "having the upper hand"? There you have it.