The implication to me was that whatever that thing was that made its way through your house and killed the dog may not have stopped at the dog, but honestly if you can theory up a cooler reason more power to you. I'm just happy the game had enough of an effect on you to have you reading into it! "I am Awake" is another one of my games that has more of a hidden narrative/story to it then this one so check it out if you wanna rack your brain a bit!
And thanks for playing, it's appreciated and I hope you had fun with it and stay curious!