Just do you best and try to learn from your mistakes. Sparring should not be any different unless your school has different rules for adults and children.

In many places you begin to spar with adults at 16.

I'm 17 and usually our instructor only lets 18 year olds to spar in the adult class, but he made an exception for me. I am quite nervous. Is there anything different that I should be know about sparring adults?