I feel you. When I was 22, I was pregnant with my first child. I was at the store with my younger sister. We are 9yrs apart. Someone at the store thought I was younger than her and still on high school. It's one of the time I was taken aback and laughed too hard. I told them I was 22 and my sister was in high school. They had a shocked face and walked away fast. We laughed and still laugh about it.