Brief Answer:
That medication takes time, would give it some more time.

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

Sertraline and buspirone are good choices for anxiety treatment. They both have an issue in common though, their effect takes several weeks to take place. Furthermore SSRI class of medication to which sertraline belongs is known to cause at times in the first few weeks what is called paradoxical anxiety, it increases anxiety instead of diminishing it. That is why they are accompanied in the first few weeks with a benzodiazepine usually (benzodiazepines are not suitable for long term use but act immediately and are suitable for short term).

So you may have a point in saying medication has made it worse, it may for the moment have actually increased anxiety, which in turn may trigger tension type headache. In addition while usually helping with headache prevention in about 20% of the patients sertraline may cause headache as a side effect.

What I would do now....first for headache I would use an over the counter NSAID like Ibuprofen, more appropriate for headache. I would give the medication a couple more weeks, as I said it takes some weeks to come into effect, so would give it a full try before declaring it inefficient. If after a couple of weeks still feeling the same then would discuss the situation with prescribing physician and would consider the use of another antidepressant instead of sertraline, like amitriptyline, a first line treatment both for anxiety and headache prevention.

I remain at your disposal for other questions.

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Brief Answer:
Read below.

Detailed Answer:
The codeine contained in co-codamol may have a role in the dizziness, it is a possible side effects (although hard to differentiate as anxiety may cause that as well as the other medications).

In terms of over the counter medications I am afraid that there aren't other options left, NSAIDs like naproxen and co-codamol are the available options. Other stronger alternatives like triptans class (Imigran) or ergotamines have the danger of interacting with sertraline and causing serotonin syndrome.
So if headache intensity is severe and has been persisting for days you might even consider presenting to the ER to get intravenous treatment to try to interrupt the cycle. Now that you say that you have a prior history of chronic headache like migraine I am afraid that over the counter medication may not be enough.

Let me know if I can further assist you.

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Brief Answer:
Read below.

Detailed Answer:
Those symptoms seem to be all due to anxiety. No they are not normal, the aim of the medication you are given is precisely to combat anxiety. But as I said at the beginning both medications need at a few weeks for effect, so would give them some more days.
In any case should try to relax. As much as anxiety affects ones quality of life it is not threatening. It may take some time to control as some medications work better in some patients than others, more then one treatment strategy may be needed to try, but you will eventually get better.
I would discuss with your doctor the possibility of being prescribed also psychotherapy sessions as it helps you to better cope with symptoms and identify anxiety provoking patterns thus making the job of the medication easier.

I hope to have been of help.

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