I don't know why but my german fluency is increasing way too fast and by fast I mean after every lesson fluency increases by 2%
and I am currently on Phrases. and have already reached a fluency of 23%
Don't worry, my fluency in French behaved the same when I started, it means nothing much though, most of people here would tell you that fluency is meaningless and you will be best if you treat it that way too. My Duolingo fluency in French right now is 65% but my real one is more like 15% (if that's even measurable).
I am seeing the same thing with German and French, but have been ignoring it.