Brief Answer:
Stress can cause your symptoms but physical causes should be ruled out first- details below

Detailed Answer:
Hello and welcome to "Ask a Doctor" service,

I carefully read your query and understand your concern. Stress may cause headaches and difficulty to focus but this is an exclusion diagnosis, which means that other causes should be ruled out first.

It is good you already had a CT scan, this will help rule out brain lesions as a cause of your headaches. On the other hand, there are a few things to consider related to headaches is your case. Uncontrolled diabetes and high blood glucose levels are a potential cause of headaches (your HbA1C is over 10, while the target for patients with diabetes is under 7). Thus, you will need better control of sugar levels as it may cause headaches and also may adversely affect your body (blood vessels and almost all organs).
I would also recommend you to have a TSH and FT4 check as thyroid problems are common in patients with diabetes and also thyroid problems may affect our ability to handle stress.
Another potential cause to consider in your case is sinusitis (as you have nose congestion). The CT scan of the head will give more information on the sinuses as well, if there is any thickness of the sinus walls present and if you have sinusitis or not (this does not determine if it is viral, bacterial or allergic but it confirms you have sinusitis or not).

Of the medications you use, hydrochlorothiazide may in some patients cause headaches but this generally happens the first few weeks till your body gets used to it and should not last longer than a month.

To conclude:
- it is good you had the CT scan, its results will help rule out brain lesions or sinusitis as the cause of your headaches
- I would also recommend you to have some blood tests for the thyroid function to make sure your thyroid functions well as thyroid problems are common in diabetes and also thyroid affects the way we handle stress.
- CBC and ERS and metabolic profile (creatinine and electrolytes, ALT, AST, bilirubin, lipids) are general tests that can be helpful to determine that you are healthy in general.
- hydrochlorothiazide can cause headaches in the beginning of its use but should not cause headache after a few weeks (you can discuss this with your doctor as well)
- you will need better control of sugar blood levels as diabetes may be related to headaches.
- if the CT scan and blood tests come out normal then you will need to focus on diabetes control and stress management

I hope this answers your query and is helpful to you. I remain at your disposal in case further medical assistance is needed.

Kind regards,
Dr. Antoneta Zotaj,
General and Family Physician

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