Mate, Cornwall is basically the ancient alien capital of the UK so you've come to the right place - we practically get these things queuing up over the standing stones here! 🛸
What you're describing sounds classic - the hovering, the way it just stays put rather than moving like a plane or drone, that's the bit that always gets people and rightly so.
Few questions that might help narrow it down:
Duration - how long was it hovering before it moved or disappeared?, Lights - single colour, multiple, pulsing or steady?, Sound - any hum, or completely silent?, Size - rough estimate relative to, say, a full moon?
I'd strongly recommend grabbing a decent night sky app like Stellarium to rule out Venus or Jupiter first (I know, boring, but she'll play tricks on you at low altitude), and if you haven't already, check FlightRadar24 for anything scheduled in that corridor.
That said, I've been watching the skies over West Penwith for years with my Celestron binoculars and there are things that simply don't fit any conventional explanation - and trust your gut, because the ". Can't stop thinking about it". Feeling is genuinely significant, people who've seen something mundane don't get that reaction.
Write down every detail you can remember right now before the memory softens - timestamps, compass direction, weather conditions, the lot. Would love to hear more from others who've had similar field-hovering encounters too, there might be a pattern developing! 👀