That feeling of not being able to stop thinking about it is real, I've had it too. Few years back I saw something over the tree line on my property in WV and it just sat there, no sound, no movement for a good couple minutes then gone. No blinking lights, nothing like a drone.
What shape was it roughly? And did it make any noise at all? Those two things tend to narrow it down pretty quick from what I've read on here.
Also if you have a camera or even just your mobile, next time it happens try to get something even if its blurry. Blurry is better than nothing and people on here are pretty good at analysing photos without just dismissing them straight away.