Sometimes I feel like I am a child with no business in this adult world
Why do you think you are a child?
I don't feel I can take care of myself.
It is ok to feel overwhelmed with adult responsibilities. If you need help there are many resources you can check out to get help.
I don't want to hear about that.  It's too stressful to think about!
I totally understand that it's hard to think about this kind of stuff.  That's why it's so helpful to find a professional to talk through these issues with, so they can give you a new perspective on but your life and life in general!  You can do this!