I used the restroom just before departing a flight recently. As I opened the door on the stall to exit a janitor was standing just outside holding a broom and dust pan. I was brief so it seemed like she appeared out of no where and was not in the restroom when I arrived. I could barely get out of the stall while she was rushing inside. I couldn't help notice how she very quickly swept the floor but more like just going thru the motions since it was clean (as in no paper or trash on the floor) then she exited the restroom after doing that. Immediately after, a supervisor (I guess) stood at that same stall and just stared inside for about 5 minutes. I was washing my hands but still could see the area. I don't know anyone else's experience. I can only speak about mine. I don't know why so much attention was placed on this stall. Maybe some high alert was up for the restrooms.