Don't feel imtimidated. When you walk in to class look around and rember everyone in the room started out at the same level, white belt. If you ever feel that a senior is being to rough or kicking you too hard tell them to back off a little. You will soon find that some of what you think of as agression my be intensity there is a bit of a difference. If at anytime you fill that someone is getting out of hand tell your instructor. I as a black belt do not fell fustrated working with a lower belt, the teach me as I am teaching them. I will back down my kicking streingth to match my opponent, I also enjoy sharing my knowledge with them. Just keep suiting up, showing up and learning.