Right so I've had similar over the fields round Pendle way, couple of years back now. The hovering thing is what gets you isn't it - planes don't hover, drones make a noise, and helicopters you can usually hear from miles off. What was the size of it roughly, like compared to something you could gauge distance on? And did it move at all or was it completely stationary the whole time?
The fact you can't stop thinking about it is actually relevant I reckon. Not in a woo way, just that your brain is trying to process something it couldn't file away neatly. Thats usually a sign you genuinely saw something unusual rather than just misidentifying something mundane.
Post any photos or video if you have them, even blurry ones are worth sharing. People on here are pretty good at ruling stuff out.