Is it normal that i think about people i used to know?

So yeah, i am not 15 years old, but obviously 18, and i moved quite a bit. I sometimes think back to the place i lived 11 years of my life. I think about the people i used to know, from my best friends to people i have only seen a few times. I really saddens me that i had to leave that place, especially since i was starting to find my spot in society. I remember a kid from when i was 6 years old, and sometimes i wonder if they ever think about me to, or even remember me.
I can't be the only one, right?