Hello and thank you for your reply.

I am a 26 year old female from MA. I have no history of concussions prior to 2008 and no history of prolonged illness or high fevers. My stress level is pretty much the same it has always been, emotional or otherwise.

I'm not sure if my injuries could be considered cluster headaches since most of the time when I hit my head I go to the ER and they tell me I have another full blown concussion.

I began to keep a record of my issues and symptoms after my first concussion and I have continued to do so. I have noticed that my injuries do not seem to coincide with any specific factor such as a late night, alcohol comsumption, feeling tired or groggy etc as you have suggested. From what I can tell they are random.

Hopefully this information helps.