I have no idea what the symbolism of the three means, or what was in the house with us. Maybe its best if I don't

Staring at my ceiling, i know for a fact, I'm not going to sleep tonight. My bottle of zaleplon sat on the desk beside me, fully empty. 

'For God's sake' I exclaim in pure frustration. This is the third night in a row i haven't been able to sleep. Do i go back to mindless scrolling on my phone? Or should I go eat something? Either way, it's not gonna happen.

BZZZZZ! BZZZZZ! BZZZZZZ!

That was the doorbell. Who the fuck is ringing the doorbell at this time? I look to my left and it's 3:33 AM. Got college at 8. A rising sense of unease rises throughout me. Slowly emerging from under my safe blanket, I open my door and creep towards mom's room, she wont be asleep she'll be playing mahjong or some shit. I slowly open the door trying as hard as I can not to make any unnecessary noise. Across the room on the double bed I see a bewildered face lit up by blue light.

'Did you hear that too?' a voice comes from the bed

'Yeah, did you see who it was?' 

'I looked, but there was no one there'

'That's weird, I'm gonna look'

Mom's bedroom window overlooks the porch and the front door so if someone was there ringing the bell id see. as i lift myself up, i realise she was right, there's nobody there. But there's something much worse. The kitchen window is wide open. We never open that window, unless I've attempted to cook something and no doubt will set the fire alarm off.

'Mom, the window's open'

'What?'

We look at each other, both horrified and anticipating the worst. interrupting our horror, we hear the stairs creaking. they're creaking slowly and it couldn't be the cats because they're too light to make a sound. We hear the creaking become closer and closer and then stop. Mom is on the phone, it rings once, then again, then once more.

'Police please, we think there is someone in our house'

The footsteps are now much louder and right outside my bedroom door, which i left open. The feet then suddenly turn back and start coming towards mom's door. Hearing  something touch the doorknob, i brace myself to whatever horrors are on the other side.