Yep agreed. I was in the bathroom and my first thought was airplane - no, too loud, building collapsing? - no, no movement - what is it? Then my GF said it was probably military jets.

Bad idea, especially with no warning. Articles about it now generally seem on the same page: https://www.bostonherald.com/2023/01/02/flyover-for-bruins-game-at-fenway-park-freaks-out-boston-area-residents-almost-had-a-heart-attack/