There is truth to the sayings "hen pecked" and "pecking order". They do argue to establish their pecking order and heirarchy in the flock. As long as nobody is getting real injuries, they should be fine. Have you been able to watch them? Do they have enough space, food, feeders, etc?
It's natural for young chicks to fight. They are establishing the pecking order. However, it sounds like your chicks are fight too much! Are they crowded? Move them to a larger brooder, keep a red light on them, offer green treats, feed fine mash, and remove any injured chicks to recover.