To have a more accurate guess at her mutation, better photos will be needed, preferably one showing her entire body from the front, face towards camera so we can fully see the chest and tummy area, and another one of her back, showing the wings and rump.
That is up to you, if you want to refer to her as a him and it's not confusing to you, then go ahead. I think you could still get used to the change.
I raised a lovebird thinking he was a she and only after 5 months did I realize my mistake. And even though to this day he has a girly name (couldn't change it because he knows his name and responds to it), I refer to him as a he.
RIP sweet Tito (Summer 2008 - January 17th 2013).
You are missed and never will be forgotten.