Is my bird's bleeding in need of seeing a vet?

My 10.5 month old male cockatiel was bleeding from and area near his tail feathers. It wasn't a lot of blood and it stopped on it's own. I think it was a blood feather but I couldn't see a broken piece still in him where blood is stained on his feathers. I could tell he was scared because he was shaking and I might have made him feel worse by freaking out, but I don't believe he is in pain. Should I see a vet to check out the wound?