Progesterone cream

My doctor prescribed me a progesterone cream and said to use it every day of my cycle, discontinue on day 25, then if I dont get pregnant start using again on day 1. Everything I've read about progesterone cream says to start using it after ovulation and discontinue if you get your period, but continue if you get pregnant. So basically the opposite of what my doctor prescribed. I've also heard starting it before ovulation can cause delayed ovulation. This month I'm supposed to ovulate next week Friday, and I leave that night for 9 days so I really dont want it to delay ovulation and I miss my fertile window this month. Has anyone done progesterone cream like my doctor prescribed? Any feedback?