Rabbit freaking out over nothing

So last night, while i wasnt doing anything out of the ordinary, Bella had a little freak out. Basically she jumped out of her litter box, thumped and into the other room and stood frozen while being completely alert. She stayed like that for a few minutes, and then walked around very cautiously after that. She did it again a couple of hours later, this time i tried comforting and talking calmly to her but she just remained completely still and acted off. She didnt come at me at all and it was almost like she was warning me of something whenever she thumped. This morning she seemed back to normal but when i texted my mom (who watches her while im at school) how she was doing, apparently she was fine until she would act scared and run and hide. I havent changed much at all in my room and there hasnt been any new noises at my house. Anyone have any ideas on what is happening or how i can calm her down?

Is this still happening? This link might be helpful: https://www.petplan.co.uk/pet-information/rabbit/advice/fearful-rabbit-behaviour-explained/

Could be as simple as her hearing a mouse, or I've even read of a rabbit getting freaked out by a spider. Rabbits have very good hearing, so she can be hearing something that you might not be able to detect.

I wonder if they can hear earmites when they have it?