I walk out my room to go to the bathroom and I practically kill myself over a plastic bag which I'm…

I walk out my room to go to the bathroom and I practically kill myself over a plastic bag which I'm guessing my father in law put there. I know my mil wouldn't have. It wasn't there at 5 this morning. But who puts a bag in front of a person's especially an 8 month pregnant woman's bedroom door with no warning?