Brief Answer:
No aneurism, probable tension type headache.

Detailed Answer:
I read your query carefully and I understand your concern.

I will start by addressing first your last question about aneurysm. Fortunately there is no reason at all to think there is an aneurysm. An aneurysm which has not ruptured doesn't cause headache (unless it's a very big one which would certainly be visible on CT, so to be excluded). If it ruptures, then it would mean a brain hemorrhage which apart from not being present on CT, would cause a very severe headache, with several other signs and symptoms. So it certainly is not a ruptured aneurysm either.

Regarding the cause, by your description it seems a case of tension type headache. It is by far the most common type of primary headache (primary meaning with no identifiable cause), it is often precipitated or exacerbated by stress. Treatment is with over the counter painkillers like ibuprofene. Also important is prevention by stress relaxation techniques, exercise and stretching, regular sleep and eating schedule. If these measures don't work and pain-killers are often required, then prophylactic treatment with a class of drugs called tricyclic antidepressants has shown good effect and could be prescribed by your doctor (the fact that it is an antidepressant doesn't mean that you are depressed, they are also used for other purposes like prevention of headaches in your case).

Other possible causes could be cervicogenic headache related to changes in cervical spine (less likely considering your age) or headache related to your poor eyesight for which glasses should help.

I hope to have been of help.

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Brief Answer:
Try to relax, forget about the aneurysm.

Detailed Answer:
I understand what you mean. It is true that a plain CT doesn't catch every aneurysm because they usually are millimetric. But as I said before an aneurysm itself doesn't cause a headache unless it ruptures. If it was of a size big enough to cause a headache by compressing neighboring structures, then the CT would've seen it for sure.

Hopefully my reasoning was clear enough for you to understand yourself (not just cause me and your doctor said so) that your headache does not originate from a brain aneurysm.

Now of course you might ask what if you have a small one anyway, independently of whether you have a headache or not, but then that could be said for any existing disease out there. I could unknowingly have one for that matter. We should consider a diagnoses when symptoms suggest it.

So try to relax, at least now that you have had the normal CT report.

I remain at your disposal for further questions. (If you do not have any other question, you can close the query and rate the answer as you see fit).

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