they say it isn't possible but...

My BOxRIR hen lays 7 or 8 days in a row, then takes one day off. The day before yesterday she took her one day off. Yesterday morning DH saw her in the nesting box in the a.m. That afternoon I went out to collect, but only my Araucana had laid. I was worried that she was perhaps egg bound, but she free ranged, ran around, ate etc like normal. Chalked it up to the sweltering heat. Today I got home (8h shift, so got home early, at 4) and went out to collect and found a brown egg in the nesting box, and another brown egg next to it!! She laid two in one day, and pretty close together time wise as well. I know it wasn't another chicken because the only other I have is my araucana. What was really odd was that one of the eggs was rough looking, and had a white bullseye pattern on it. I tried to take a picture but the flash washed it out. Weird.