Brief Answer:
Cold may be responsible for your headache.

Detailed Answer:
Hello
Welcome to Health care magic.

It seems from the history that you are having headache on the left side of head.
The common causes for headache are cold, sinusitis, uncorrected refractive errors, inflammations of eye, primary headaches like migraine.

Since you are having cold it may be the cause for headache. The treatment of the condition is by use of analgesics and decongestant anti cold drugs.
If the condition does not respond to treatment eye examination is required to find out any refractive error and its correction.

Hence as of now you need to use analgesics and anti-cold drugs.

Hope the information is helpful to you.

Thank you
with regards

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