size of bantam brahma eggs

ok I just don't know if she is laying or pretending/practicing could a bantam brahma pullet lay an egg the same size as a BO hen? her 1st few eggs?
she was in the coop making lots of noise sitting on the other egg that was in the nest, I had to go out and when I came back the brown egg was there I wasn't here to see if the BO went in to lay so I just don't know whose egg it is, the bo doesn't always lay 3 days in a row and I haven't had 2 brown eggs in 1 day yet so the girls aren't helping me. I was so excited seeing her squeaking .