How long after a motor vehicle accident would you expect symptoms including memory loss, hypersomnia, and mood changes to be attributable to the accident?  

I would love to have the answer to this. I can tell you what the Headache Classification Committee of the International Headache Society says:Post-traumatic headache (PTHA) is defined as a secondary headache that develops within 7 days after head trauma (or after regaining consciousness followi...