I'm confused

So hi, I haven't played this game in a long time. But, with the new update out, me and my brother decided to play again and now I'm confused. You see, we joined a lobby together and around like door 16 we encountered Ambush, I didn't think we could even see Ambush this early so I was wondering how that happened, then the next game it happened again, with Ambush coming around door 22, at this point, Im very confused, but that isn't even the end of it. The next game, some time after the seek chase, the window monster (I think there name is Sally) came and attacked us, I didn't even know that could happen. (I assume it was because of a previous update) So, after we die, I go to sleep and that leads me to right now, where I just left the game to write this after the window monster attacked me at door one, sooo.... Is this normal? Or did I just get lucky?