Babel: The Dream

I want to share my dreams with you today. Well actually, I want to share the language of my dreams. I have troubles to remember in which language my dreams were - or to be more accurate in which I and other people spoke in my dreams. I can remember what was said, but in which language it was said I can't remember. The only way I can help myself is by concluding indirectly through clues.
For example, some months after I moved to the US, I had a dream in which I was talking to a man. I know that the man can't speak German. When I woke up, I could remember what I said but not if it was in English or German. Since, that man can't speak German in real life, it would be consistent that I spoke English with him in my dream. But that was not the case. I was talking very respectful with him in my dream. For such cases, in German the word "Sie" is used for the English word "you". It is a more respectful "you" compared to "Du". "Du" is used if you talk with friends. "Sie" shows also more distance than "Du" and is therefore used if you talk to strangers. In Farsi there are also two forms for "you": شما and تو. In English there is only one word and hence I was not talking English in my dream.
Today, I had a dream in which I was teaching a children class. Here, again I remember what I said but not in which language. I remember that I had to struggle for finding the right words. If I would speak German, I wouldn't have problems to say the things I said in my dream. And from that I conclude that I was dreaming in English.
Are my conclusions correct? Do we dream really in one language or do we dream only the content without the "wrapping" language? If the second case is true, my dream was that I have talked in a respectful way with that man and I made the false conclusion that I was respectful because I used "Sie". And when I had problems to find the right words in my dream, I was reliving the everyday experience I am confronted with since I am in the US. So dreams would be a communication without any words.
What do you think? Do we dream in a language? If yes, what is your dream language?