Husband is unsure about my brother now

I (34f) may have underestimated something that I told my husband (37m), and now he’s in a weird place and I don’t know what to do about it.

Growing up I was very close to my older brother (still am). He’s 2 1/2 years older than u am. We lived in a small house and shared a bathroom, and in our teen/ high school years one of us was always coming and going into the bathroom it seemed, especially before school or on weekends before going out.

He and I settled into kind of an open door policy with the bathroom, where if one of us was in there the other could just do the “knock knock” verbal thing and pass in and out, or brush teeth or do makeup when the other person was in there.

I mentioned this in passing over the weekend and my husband thought it was very weird. He asked if we’d do that even when one of us was showering, I said yes. He asked if we saw each other naked, and before thinking I answered “all the time.”

He’s been quiet since I told him this and now I regret being fully honest. He said my brother was older, and should have been the “grown up” about the situation.

Is this weird? And is there anything I can do to reassure him?