Brief Answer:
possible causes explained below...

Detailed Answer:
Hello and Welcome to 'Ask A Doctor' service...
I've gone through your query in details...
I can understand your concern...

Well, at this outset, considering your age, there can be a number of causes behind this...

First of all, it's important to know if this is happening for the first time or not...if only for the first time, then the blood pressure needs to be checked as a priority (even more important in case you're taking any blood pressure lowering medications)...

However, if it's happening intermittently, then there could be some migraine/sinusitis related concerns...to some extent any pinched cervical nerves can also give rise to such headaches (especially if it's spreading down towards the neck)...

Another possibility would be a sudden exertion which may cause stress hence giving such headaches (in that case a mild pain-killer as ACETAMINOPHEN and ample rest would suffice to control it)...

So, at this outset, I'd recommend to please check the blood pressure readings first (if found elevated, then a serial reading should be obtained and antihypertensive medications should be considered accordingly)...

Take a mild Painkiller (eg. ACETAMINOPHEN i.e. Tylenol), avoid any strenuous activities and stay rested...in case there's any recent history of flu/nasal congestion, take some steam inhalation, drink plenty of warm liquids (broth, soup, porridge) additionally...observe how you stay afterwards...

Let me know if I can assist you further.

Take Care
Kind Regards

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