Seeing floating object in bed

I'm 34F, 5'8, 150lbs, no serious medical issues, recently got off Prozac but this has been going on for over a year so I don't think it's related.

My issue: while falling asleep or in the middle of the night, I wake up and see something floating right in front of my face or above me. It's often a spiky ball or spider looking thing that's floating (about the size of a golf ball). It always scares me and I jump away from it, swat at it, and turn on the light. But it's nothing. It's always in the dark and mostly happens at home, but has happened in a hotel once too.

This has occurred maybe 8-10 times over the last year and really starting to scare and upset me. I'm at a loss of what could be causing it since I typically sleep well. I'd be extremely grateful for any ideas.