“She’s been a judge for 14 years - how can that be?”
Not a federal judge.
The distinction between Federal and state judges isn’t terribly relevant. There have been SCOTUS justices before without any Federal experience. Heck, without any judicial experience at all.
Experience as a state judge is actually completely relevant as you’re required to interpret the intersect between state and Federal law, something SCOTUS has to address regularly in many cases.
She has been an appellate-level judge for that entire tenure of 14 years. She doesn’t have to be a “Federal” judge to be a judge and have an judicial record.