Hi, I don't think it is possible, boys and girls usually separated between 10 and 12 weeks, mainly because they start humping/fighting and boys can be fertile from quite early even 9 weeks for some breeds but I don't think girls can get pregnant before 12-14 weeks so your girl should be fine at 8 weeks.
It wouldn't be good for a girl to get pregnant that young as she's still growing herself and she's not ready yet, youngest girl I personally knew was 5,5 months when she kindled so she's got pregnant at 4,5 months, it was an accident and I've got her when she was already pregnant. She had all healthy 5 babies and she was a very good and extremely responsible mother.
She was a dwarf mix.
As a breeder you are responsible for not letting your rabbits to breed at such young age so boys must be separated from girls at 10 weeks, girls can still stay together until they start getting territorial or aggressive to each other sometimes until 4-5 months sometimes until 7-8 months depending on their personalities and when they start to mature, boys usually need to be separated from each other at 10-12 weeks as they start humping/fighting, some dwarfs can start earlier at 8-9 weeks so no need to risk them if you see signs please separate so they don't develop bad habits. Some rabbits are more calm than others and can stay together until 5 months but you need to watch them closely if any sign of aggression separate immediately. If you have no experience it is best just separate girls from boys at 10 weeks and boys from boys at 12-14 weeks or if they start fighting earlier.