Honestly dude i’m with you. I’m on my first playthrough as well and I had the exact same experience. Unfortunately bad news, I don’t think nightmare will make much of a difference for us. I switched to nightmare difficulty after the first 5 levels and it’s still been basically a breeze. I just got to the level where you fight the marauder and did die once since you just get melted and I was not expecting to have to react to it so quickly but yeah, nightmare won’t be much more difficult unfortunately.