It doesn't matter

Because you're ready for whoever—whatever—is coming. You didn't want it to come to this, but if you're going to have to face this, you'll stare it down.

You came here without thinking it through, but it was the right place to wait for this. Your parents' bedroom has the nicest bed. It's the furthest room from the front door. But most importantly, you remembered just in time, your dad keeps a loaded handgun in his nightstand drawer.

You're holding it in both hands now, pointing it at the bedroom door. It's a 9mm Glock G17; a good simple reliable piece. It only has moderate stopping power (though plenty to stop a human) and the seventeen round magazine makes up for any shortcomings. You've checked the safety a thousand times and when the handle start to turn you open fire before you even realize what's happening. You blow seventeen holes in the cheap hollow core door, and at least a few in whatever was behind it.

You leave the empty gun on the bed as you make your way over to the door. Turning the handle, yourself this time, you swing it open.