Go to your college’s counseling center first thing today and make an appointment. Keep the appointment. You will probably have to wait a couple of weeks, because there are tons of other kids who feel like you.
Please read this: http://talk.collegeconfidential.com/college-life/2016222-to-those-who-feel-lonely-homesick-friendless-think-they-chose-the-wrong-school-etc-p1.html
You aren’t alone.