Yes. A few studies have linked head injury to an increased risk of clusters. But you've said you have had 'a very serious headache' since the injury ... is it a cluster?

I had an interesting experience early last spring - was in remission for ~5 years, never had gotten clusters any time other that summer. I had a vitamin lodged in my wind pipe and was choking ... I vomited, some of which got pushed through sinuses and out nose. A few days later, I went into cycle.  I am certain the acid rinse to my sinuses led to that bout of cluster headaches. Anything that injurs or inflames the nerves can be a factor.

I’m not aware of research on head trauma and the triggering of CH cycles.  Research articles I've come across indicate that the number of CH patients reporting some form of head trauma makes it something that shouldn’t be overlooked as a potential factor in the disorder.  Unfortunately a direct link between head trauma and CH has not been established.
               
Possibly??  Most notable to answering your question is that a majority of CH patients reporting head trauma also report long intervals of time between the actual head trauma and the onset of CH.  Immediate triggering of CH symptoms by some form of head trauma in not commonly associated with the onset of CH.
 
The best advice I can offer is see your doctor, endure the battery of tests and let us know how things progress.

burnt-toast
(Tom)   

that's SUCH a good question!  I never would've even thought of such a thing... unless I had a recent head injury.
Good luck to you.

Well, I fell, hit my head, got a concussion (enough so that I had to go to ER in an ambulance) - got a CH on the way to ER in the ambulance (I"m chronic) and "acted up" in the ER till I got something done for the CH (they had me strapped down to that board and I couldn't move my head - not good! Luckily the nice doc KNEW what CH was - lucky for the ER! and the nurse I was choking!)

Afterwards I visited my neuro and he ran an MRI and it seems that some more problems had arisen (he said due to the fall)... I had developed Post Traumatic Concussion Headaches along with Migraines to go with the CH. That was about 10 years ago and I still have them periodically, so I'd say a head trauma CAN trigger a CH or other things in your noggin'.

Best advice (and it's already been given here) GO SEE YOUR DOC and get a SECOND opinion from him/her. We can only tell you what OUR experience is, but he/she can RUN TESTS and FIND OUT what the problem is.

Let us know how it turns out.

Hugs BD