IMO, when the traditional roles are reversed (not a bad thing), then as a male you will need to learn how to not orgasm during the act and conserve and save it for the end.
Another thing you can use in your arsenal is soft restraints (if she doesn’t comply willingly [but obviously consensually]), and then edge her over and over, so when you do use and attempt penetration, it is “big”.
The advantage you do have (over the opposite way around) is if you have female friends (platonic) you can ask them how they handle the imbalance since women “traditionally” have been doing this for years, given male sexuality can go to excess (on average).
I would also look at getting toys, and don’t fear wearing a strap-on, and if she throws a temper tantrum, well that is on her (and not you).
Be proud that she is beautiful, safe and happy with you to the point that all she desires is to copulate like crazy, but you are correct … it is a beware of what you wish for moment.