[NonValueAdded]

Newton's First Law is likely behind the "float." Either her hand imparted motion on the bag or, as it was traveling with her and thus matched her motion, she lost her grip and as she manoeuvered to regrasp it, she changed her vector relative to the bag, thus the "float."

In low erf orbit, the erf exhibits the greatest gravitational pull so as long as she didn't chuck the bag at escape velocity, its orbit will decay until it encounters sufficient atmospheric contact to burn it up.

[A knight without armor]

Oh you mean the astronaut moved away from the bag as much as the bag moved away from her? I never thought of that. Space is so hard for me to comprehend. For some reason I was raised picturing it flat like a pancake with our Sun in the middle and our planets neatly lined up. You know those movable planet models in school. But then I remember how there is also space all around us like an infinite ball, not just, as it were - a big flat pancake.