I don’t know if I should use plain old R51 (headache) or a more specific code like G44.309 (Post traumatic headache, unspecified, not intractable)

This patient fell while skiing a month ago and has had a persistent h/a on the right side of his head. The dr did order a CT scan, which I don’t know results yet. The assessment is:
"Persistent right occipital headache after fall". If it helps, the setting a family practice clinic.

I would love to hear some opinions.

Thank you!

Amy