Low hovering triangle multiple lights over subhurban area

I was out with a puppy, potty training. I was sleep deprived and feverish in the midst of a cold, just wishing the pup would hurry up.... But I heard a quiet dual tone mechanical hum overhead and looked up to the sky. There was a black craft with a few lights along the sides, I coudn't see the shape but guessed the edges with the lights; it was shaped like a triangle. I did not recognise this an as airplane shape, and it was very low in the sky and slowly moving toward my house, I'd say curently 1-2 houses over. It was a dark craft at night so judging sizes and distances is hard but I'd say less than 500ft up and roughly the size of a house? I got scared and forced the puppy back inside and locked the doors and drew the blinds. Geting my phone inside and snapping a picture never even crossed my mind... So i have no proof and am now wondering what i really saw. Googling the description however revealed that this seems to be a fairly common sighting and I now ! find it important to report.