Don't let your parents have too much control over your life. You are in college. You are an adult. You need to make decisions for yourself. While at times you should take your parents' opinions into consideration, you need to make your own decisions. If they want you to major in one thing but you want to major in something else, you need to make that decision. It is your life. In the end, you have to live with the choices you make, so make sure they're yours and not your parents'.
Talk everything out with your roommate in the beginning. Ask all of the awkward questions within the first week. It helps you avoid awkward situations later on. Discuss everything from how you feel about music playing in your room to what your sleeping schedule is like to how you feel about having boys in your dorm. Some conversations are a little uncomfortable, but it's better to get them out of the way in the beginning so you won't have misunderstandings in the future.
Allow yourself to meet people, even if you're an introvert. It's a lot nicer to have a lot of people you're friendly with. Also, give people a chance. Even if they remind you of people you know from high school that you don't like, give them a chance. They may surprise you. Also remember that everyone has reasons for the way that they act, and keep that in mind before you judge people.