I think you win a prize for earliest “did I make a mistake” post, in terms of days you have been there. My D goes to a pretty sporty school and has zero interest in sports. She was full of doubt and had to tough it out. Bu Tgiving, we knew she would be ok. Go to as many activities as yiu are comfortable with, and just take it a day at a time. You would be be unwise to back out on the first day. And your paretns would agree.