Hi, TEB!
I'm not one of the admissions counselors, but I'd figure I'd put in my two cents as a college senior at Hopkins and a "Catholic school product" (so to speak). I went to a Catholic, diocesan-administered, co-ed high school in my Connecticut hometown that offered a total of eight AP courses. Meanwhile, my younger brother (who's now a college sophomore at another university) went to a Catholic, Jesuit, all-boys' high school in Manhattan that was quite competitive and definitely a far better choice than both the public and Catholic high schools in my hometown as far as academic rigor goes.
Based on my experiences, his experiences, and the experiences of our peers, I think it's best for students to attend the high school that provides the best academic challenges possible (within their parents' means, of course). While it's harder for a student to stand out in a more challenging school, the rigor will invariably help out the student in the long run. It was much easier for me to stand out in high school than it was for my brother, all right, and it may or may not have helped me a bit as far as being noticed by college admissions goes. (I don't know for sure whether that's the case. Who knows? There are lots of factors that go into college acceptances/wait-listings/denials.) Anyway, as far as dealing with the rigor of courses, I found it harder to adjust to the rigor of Hopkins than people I know here who went to competitive high schools like my brother's. My brother and his high school classmates, meanwhile, proved to be among the people at their respective colleges and universities who adjusted most quickly to the schoolwork.
By the way, admissions counselors at Hopkins are divided into regions; I don't know if that's the case at other colleges and universities, but I'm aware that's the situation here. Thus, the admissions counselor from Hopkins who'll read your son's application will be aware of the rigor of his high school compared with other high schools in the area where you and your family live.
The bottom line is that based on what you wrote, I don't see a reason for you to doubt your decision. You made it with the best intentions, and your son is going to a high school that sounds like it will prepare him well for college (wherever he goes). At this point, I suggest that you continue to support him as he finishes high school and goes through the college application process.
I hope this reply gives you some peace of mind! :)
P.S. Also, regarding the "getting into college" part, a much higher percentage of people from my brother's high school went to competitive four-year colleges than from my high school. Even though it was harder for them to stand out among each other, they still had a good enough academic background to get into top schools.