Prayers sent...that you will do what you know is right. Just because 'everyone does it' doesn't make it legal...be different. You're in college and you're wanting to become an individual, so stop being like everyone else.
As to being an introvert, I see that more and more among people your age (assuming you are of 'normal' college age; meaning you didn't go later in life). Look people in the eyes when speaking to them; Start reading self-help books on how to build your self-confidence...heck, even saying positive things about yourself while looking at yourself in the eyes will help. You might also try beginning an exercise program, if you don't already have one...it will help you build confidence, and possibly make new friends.
Good luck on the test.