You Are In Stage VII
You may not be a full fledged adult, but you are in the same development stage as those in their 30s, 40s, and 50s.
You've reached the point in your life where you worry about stagnation. It's hard to keep growing and improving.
It's likely that you're going through some sort of "midlife crisis" right now where you're examining your life carefully.
If you are able to figure out what you want from your life, the years to come will be much more enjoyable.