My rooster has been with his flock of 4 hens for about 8 months now. Two nights ago he didn’t go into the coop. I led him in and he went inside and flew up next to the girls. The next night he went in but would only sleep on the ground & same thing tonight he is sleeping on the ground again (floor of their coop) He’s himself during the day & is eating and drinking water and everyone’s poop looks normal. He just isn’t sleeping next to them like he always has. What could be wrong with him?