Depending on your setup it might not be enough. I have those in the bedroom, but I can't install them on the rest of the flat (they're not the most beautiful). Leaving the bedroom door open for proper air quality leads inevitably to light coming in from other rooms. Yes it's that bright in Berlin at 4am in summer. Therefore I second the mask. There are a lot of option that are super comfortable and cheap on Amazon.
What about your rouladen? Articulated steel blinds block quite a lot of light, don't they?
You mean "Rollläden", Rouladen are the rolled meat things.
Are you sure they're not the same thing? I'm quite certain I've heard people talk about "beef curtains."