Hello Erica. Hope it turns out that you do not have cluster headaches.
Yes, it is possible to have once-a-week attacks, especially for someone new to the game. If cluster headaches are what you have they may (probably will) increase in frequency.
On the left side of the screen is a cluster quiz button. Please take the quiz and let us know the results.

It will help us to direct you to good sources of assistance if you will tell us where you live (city & state, if U.S. or country). At the Home page: Help button-->Edit & Profile --> Location. (This will add your location, just below your name, every time you post a message.
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Unfortunately, it's not quite so simple. ER's have a terrible reputation for the accuracy of the Dx made around headaches.

I would not accept their diagnosis of Cluster--and then start treatment--without conformation and guidance from a doc with experience treating complex headache disorders.

Two issues involed: need for an accurate diagnosis and the reality that IF you have Cluster you'll need a good doc to work with you for years. Cluster is not a treat-and-cure disorder for it usually continules for years. The good news is that, with skilled care, we can have a good life.

So, I'd urge you to seek, if at all possible, a headache specialist. Avnoid general neurologists:not good success rate around here. IF a HA specialist is avaiable, then ged back.
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LOCATING HEADACHE SPECIALIST

1. Yellow Pages phone book: look for "Headache Clinics" in the M.D. section and look under "neurologist" where some docs will list speciality areas of practice.

2.  Call your hospital/medical center. They often have an office to assist in finding a physician. You may have to ask for the social worker/patient advocate.

3. Multimedia File Viewing and Clickable Links are available for Registered Members only!!  You need to or ; On-line screen to find a physician.

4. Multimedia File Viewing and Clickable Links are available for Registered Members only!!  You need to or Look for "Physician Finder" search box. They will send a list of M.D.s for your state.I suggest using this source for several reasons: first, we have read several messages from people who, even seeing neurologists, are unhappy with the quality of care and ATTITUDES they have encountered; second, the clinical director of the Jefferson (Philadelphia) Headache Clinic said, in late 1999, that upwards of 40%+ of U.S. doctors have poor training in treating headache and/or hold attitudes about headache ("hysterical female disorder") which block them from sympathetic and effective work with the patient; third, it's necessary to find a doctor who has experience, skill, and a set of attitudes which give hope of success. This is the best method I know of to find such a physician.

5. Multimedia File Viewing and Clickable Links are available for Registered Members only!!  You need to or NEW certification program for "Headache Medicine" by the United Council for Neurologic Subspecialties, an independent, non-profit, professional medical organization.
        Since this is a new program, the initial listing is limited and so it should be checked each time you have an interest in locating a headache doctor.
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WHY A HEADACHE SPECIALIST IS RECOMMENDED


Headache. 2012 Jan;52(1):99-113.
Cluster headache in the United States of America: demographics, clinical characteristics, triggers, suicidality, and personal burden.
Rozen TD, Fishman RS.

THERE REMAINS A SIGNIFICANT DIAGNOSTIC DELAY FOR CLUSTER HEADACHE PATIENTS ON AVERAGE 5+ YEARS WITH ONLY 21% RECEIVING A CORRECT DIAGNOSIS AT TIME OF INITIAL PRESENTATION.
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Print the PDR file, below. Use it to guide your talk with any doc you see. AND don't start treating yourself until a god doc has confirmed the diagnosis for you need to work with the doc and not independantly.
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As you have time, explore the buttons, left on this page and start exploring the following:


These sites which are worth your attention: medical literature, films, plus the expected information
about CH.

Multimedia File Viewing and Clickable Links are available for Registered Members only!!  You need to or
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Multimedia File Viewing and Clickable Links are available for Registered Members only!!  You need to or Search under "cluster headache"
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Multimedia File Viewing and Clickable Links are available for Registered Members only!!  You need to or
  Full of articles, blogs, book: written by one of the best headache docs in the Chicago area.
  Worth exploring. The latest book is in e-book edition, $10; comprehensive and worth buying for
  a careful read.
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Multimedia File Viewing and Clickable Links are available for Registered Members only!!  You need to or
  A new site (ca. 2015) with extensive material. Explore the site map and then patiently
  the broad range of materials.