Thanks for your reply.
There can be two possible diagnosis on the basis of information you have provided. With the history of throat irritation the sinus infection can cause this. The other possible cause can be temporal arteritis but less likely because you have it on left side only. The area of your pain is not a classical one for the sinus headache but fairly possible. Anyhow a doctors visit is necessary for investigations like ESR, sinus xrays or CT to see the status of that area. But donot worry hopefully nothing will be serious and you will get fine once treated on right lines. Till you visit him you can take Tab ibuprofen Thrice daily. You can start with Tab citrizine once daily to help you with allergies. Both are otc and can be taken by nursing mother. But Since it has been going on for few months, its recommended to see a doctor. Initially you can see PCP and later he can refer to ENT doctor or neurologist as per suspicion.
I hope this helps you.
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