Wyatt0224
Chirping
As people before have said you just broke up the pecking order that the older girls had and therefore they will be aggresive in making a new one. Since they're so old it may take time for the older hens to accept a rooster. My aunt had an accidental rooster once and the old girls would try and kill him every day. It will take quite some time but the hens will eventually come around to respecting the rooster and he will be at the top of the pecking order. As long as he is nice I wouldn't get rid of him.