First realize they are living animals with their own personality and living in unique conditions that can be different for each of us. They don’t always act the same.
There are a couple of things that could be going on. The mating behavior is not just sexual. It is a show of dominance. The one on top is dominating the one on the bottom. Part of what is going on is that the rooster is trying to take command of the flock. He has to be the dominant chicken to adequately perform his functions as flock master. I’ve seen mature hens “mate” other hens to show their dominance when the flock does not have a rooster that can dominate her.
A “normal” mating sequence is that the rooster dances to indicate his intentions. The hen squats to spread herself on the ground. This spreads his weight out so even if he is bigger than her the extra weight is not a problem.
The rooster hops on and grabs her by the back of the neck. This neck grab helps him keep his balance and gets him in the right position, but it also signals her to raise her tail out of the way.
The rooster quickly touches vents and hops off. The hen stands up, fluffs up, and shakes. This shake is not her telling him “I’ve had better, Big Boy.” It gets the sperm in the right position in her system.
There are a lot of variations to this. Sometimes the rooster dances and the hen runs away. The rooster may then ignore her and go about his other business. Or he may chase her and she squats after a few steps. She just wanted to see if he really cared. She may keep running and he finally quits chasing her. Or he may eventually catch her and kind of force her. As long as she winds up squatting and not hurt it all works out.
As you can see, it takes both the rooster and the hen to do their parts. It’s possible the rooster is just a brute and you need a different rooster. It’s possible the hen never learns to do her part and that caused unfertile eggs and unrest in the flock. I’ve solved problems with this by removing the hen. The rooster was fine with all the other hens.
With the age of yours you have something else going on. They are all juveniles. They have hormones going crazy and no self-control, especially the rooter, or with the pullets, the hormones may have not kicked in yet. A whole lot of roosters are killed at this stage when, if you let the flock mature, they would grow out of it.
There is even something else going on, back to the dominance thing. Different chickens mature at different rates. For a mature pullet or hen to submit to a rooster, that rooster often has to show certain good traits. Some hens will squat for practically anything wearing spurs but many require a rooster to dance, to find them food, to watch for predators, and to keep peace in the flock before they will agree to let him father their chicks. I’ve had roosters at four months that mature hens would accept. I’ve had roosters at nine months that mature hens would not accept.
Back to your basic question, are you going to see more eggs soon? Probably. I’ve seen 13 week old roosters “mate” 13 week old pullets when the pullet was not close to laying. But that mating behavior is an indication it could happen soon. Not a guarantee but a good indication.
