Has anyone else had a moment where they realized they didn't know something basic about their own anatomy?

I’m 22 years old, and I just found out that people with vaginas have three separate holes—the urethra, the vaginal opening, and the anus. Somehow, I went my entire life thinking that urine came from the vagina, and I never questioned it. Now that I know the truth, I feel a mix of embarrassment, frustration, and disbelief.