If she is she is and you can't get a vet to tell you because they don't really know.
You are doing the right thing in separating here because it sounds as if, even if they are the same sex that one is bullying the other anyway. They will be really fine along so don't fret.
For now you need to prepare her in case she is expecting. If she has babies you will cope and so will she. Teen mums do just fine. A young female may have a smaller litter if she is pregnant at all and you will manage to home them. You could even keep a girl with mum and a boy with dad
When you get her in the new cage alone count 22 days to be safe then assume that if no babies arrive she is not pregnant. I'd move her rather than him so she has no scent of him to worry about around the cage.
Remember though that same sex animals will 'mate' or mount each other as a dominance sign so they may still be two males but regardless they need separated for their wellbeing.
Keep us posted how she does.