Air carrier Flight Attendant reported a box fell on their head during descent through turbulence and the aircraft experienced a hard landing.

Narrative

During the flight from ZZZ1 to ZZZ; I worked at the aft galley in the 2L position. We experienced turbulence while flying near mountains; and it was quite windy. When I glanced out the window; all I saw were clouds. The next thing I knew; we were on the ground. The descent felt abrupt; like we were 'sucked down.' One of the overhead boxes fell on my head; which was surprising since I had thoroughly secured and latched everything in the galley.As part of my routine; I meticulously double-check the galley; ensuring everything is secure; and I also verify that my coworkers have done the same. On this flight; my coworker and I confirmed that the galley was secure. Additionally; I learned from another coworker that she heard 'Terrain; terrain' from the flight deck; which likely indicated our proximity to the mountains. She described the landing as intense; almost throwing her from her jump seat.The landing was indeed rough; shaking the entire plane. Purser mentioned that multiple passengers commented on the unusual severity of the landing; noting it was unlike any they'd experienced on flights to ZZZ. While acknowledging that turbulence can be unpredictable; the Purser expressed trust in my thoroughness in securing the galley. The force of the turbulence and hard landing may have contributed to the box falling.