That would weird me out too. She must have had a stash of some sort in that bag to be so worried about it arriving before her.
And middle seats are the absolute worst!
Hate them middle seats. We were about to pull away from the gate, and they let us move around to fill some empty seats... I got an aisle with nobody in the middle.
But then a bunch of late-comers boarded at literally the last second... and I had to go back to my middle seat. Nuts. :-)
It's what i get for waiting too long to ticket my flight. I get much better seating if I get it more than a week in advance, but this one I neglected until like last thursday... my own dumb fault it is.