I don't want to grow up… ?

I turned 18 today and I don't wanna grow up. It is depressing because i'm not young and cute anymore and everyone expects me to just be responsible and act like an adult. i dont know why! I wanna get over it and stop crying about it, but I cant. I just dont wanna leave my home and parents and everything! I wish I could not grow up and go to Neverland! I hate my birthday and I have felt this way since I turned 14…I feel old and I miss the fact that when you are a kid the only thing you are worried about is the next toy you are going to play with and stuff.. being completely innocent and getting lots of hugs and kisses…
How do I get over it and are there others who experience/have experienced the same thing?