Scared about having help?

me and my boyfriend are 20 and we want to have . However last time he was going to insert it i totally freaked out and didnt let him. A few months ago i had a cather inserted in my bladder through the bsically it killed and wasnt plesant i could feel the wire going in and am really scared that is going to hurt alot aswell? ive tlked to him and he sys he will be gental but am extremely scared is it going to hurt? and will it hurt after.