What is growing up

I have recently moved to Holland, and I am living my own for the very first time. And I am living alone, in a small rented room, a few minutes away from the university I am studying at. I have finally reached "adulthood" or maybe "young adulthood".
And the fantasy we all create when we are small, that when we live alone it's like we all grown up, we feel like adults, and ready for anything, turned out to be a lie. I don't feel older, or wiser, and I definitely don't feel ready for anything. I do feel scared, afraid of failing, of doing something wrong, and I feel alone and misunderstood. 
The good thing is that I am sure I am not the only one that feels like this, and it comforts me in way. It's like a can the define the feeling of being okay. I don't feel great, but I also don't feel sad. I feel prepared for the upreared, I feel ready for the mistakes and I feel friendly with the loneliness.
And so I wonder, if this is what growing up feels like. When you experience a huge change in your life, but you don't quite feel it like you imagined. You feel both calm and unsettled about it. You feel free.