Growing pains encompass a lot of different things such as literal growth spurts, discomfort, evolution, depressive moments, freedom, adventure, maturation, and a myriad of other qualities that involve vast progression. As you grow into a more adult version of yourself, you start to walk on your own path to the beat of your own drum. You look different, you act different, you speak differently, but you are still you. You will notice that your relationships will start to change as you bounce through different parts of life including those with your "friends", your colleagues, siblings, parents, but also (and probably most importantly) yourself.
Many of us realized one day that we have vastly changed indecent years. Some of that is due to life molding you, and some is because you're growing up.