I will give this bluntly but it will do you some good.
If you are unsure about taking a fight then you are not ready to fight.
I was offered a shot at something similar to you and accepted right away because I knew my instructor doesn't ask you if he never thought you had a shot at loosing.
If you are nervous then that is another sign that you are not ready to fight.
Throughout life there are bumps along the way some may be painful...others not...who gives a damn in the end you'll still die