I wouldn't say so, seems about right. Financially you should be getting sorted as they hit 20s, you'll still be youngish, as you will as they grow up and you'll have the 38 years of experience and will have hopefully got most of the things you want to do without kids out of your system.
I had my first at 24, last at 30, I felt much better with my last, maybe just experience, but yeah 38 sounds good and if like me, having them will be the best thing you can do in life.
Congratulations Theo555!