Totally normal. Isn't brewing fun!
Just because it's a lager yeast, doesn't mean it won't form a krausen or cause a blow off. I like using fermcap-S in my wort to prevent the krausen from raising much over 1" of headspace.
Beer so good, it's frightening.
2014: Seven Heavens Series One: Vilon, Mystic Melomel, Skeeter Pee.