Months is your answer, especially if she hasn't grown follicles yet.
My females wrap water bowls several months before ovulating, keep pairing it's really early in the process.
Probably 50% or more of the pairings you do will result in nothing happening, that's just how it goes.
They will lock up as the season progresses and the more they do the better for you, but don't be alarmed because after 2 weeks they don't seem interested in each other.

Feed her well this time of year, I'm offering my females 2 times a week and some are eating 2 small rats each time offered.