Hi, Fisrt time raising chicks. Have 21 from McMurray hatchery that are almost 4 weeks old. Moved them today from the basement to their coop. Put them all in a big pet carrier to move. After I took them all out I saw some leaving bloody-looking droppings. They were all vaccinated for coccidiosis on day 1 & I feed unmedicated feed. None are acting lethargic or off, but I wonder if stress can cause this? Some are exploring the coop more & some hanging out against the edges. When should I be concerned?