I recommend fasting, and praying for God's protection. I can't say for sure what it is, but based on my own personal experience, it doesn't sound like anything good. From my experience, Angels never really make a ruckus, and God doesn't need to get your attention through this way. He can do it anyway. Probably, the best thing you can do, like I suggested, is seek God's protection. As it says in Romans 8:31, "If God be for us, who can be against us?"
I have seen and heard spiritual beings my entire life. I have had similar experiences to yours. An example being, one time, when I was just 11 years old, I was in my bedroom, lying awake in my bed at 1:00 AM in the morning. No one else was awake. My bedroom didn't have a door on it, so I could hear pretty much every major noise in the house. Suddenly, from the kitchen, I heard what sounded like a glass cup hitting the floor and breaking. I imediatly got up and went to the kitchen to see what had happened. I checked everywhere, even the dinning room, and found nothing. Not even the slightest sign of broken glass anywhere. My family and I saw many more bad things in that house before we left. My father also had the same experience I did in the house we lived in prior to this one, when I was just a baby.
He was home alone, and he suddenly heard a glass break. He checked the entire house, including the windows and mirrors, and found nothing broken. My family and, also seen and heard MANY more bad things in that house, than the one that I mentioned above. Turns out, in both houses, the people who lived in them long before us did horrible things in them.