The spots are a sign of calmag def, probably. Definetly not connected to the overwatering. If she was droppy for a day, thats a tricky care i cant say thats what happened but hear me out.
When a plant takes in a lot of water, after a long dry period she drops because parts cant keep up with the sudden intake of water, doesnt mean she is overwatered necessarily, could also mean she was slightly underwatered before. You can read about that stuff everywhere since its not only a cannabis thing, its an overall plant thing
Besides that i dont think you can overwater a pot the way you watered, i ALWAYS water with 10%runoff, as soon as my plants are big enough for it. I sometimes dump 6liters in there and they never overwatered, that can only happen if you water too often and inbetween they cant breath.