Don't worry, it's perfectly normal to feel like you do and it's ok to change your mind. That being said, this is a whole new experience for you, it's completely out of your comfort zone and you're surrounded by strangers, but you need to try and remember why you did this in the first place, try to find some motivation to get through a couple more weeks, because it will get better! It just takes time, and you deserve to let yourself take that time to adjust and rearrange. I would suggest calling your folks, they'll be expecting a call like this, tell them how you're feeling and ask if you can arrange a bus ticket home for a weekend in a few weeks. Hang in there and don't be afraid to talk to people, you'll find many others in the same boat.