Thanks for providing additional information.
I understand your concern and it's my pleasure to help you in every aspect.
As per your description,very few possibilities can be suggested such as an Abscess in initial stage,kind of tumor growth, an aneurysmal temporal bone cyst, a mild reaction to an irritation or a certain kind of infection, or any tiny blood vessel occlusion.
As you have slight headache and vomiting so you should consult your family doctor for a clinical exam.
And in the meantime you can take OTC Motrin 200 mg every 6 hourly.
Also apply warm compresses on lump.
Your blood pressure should be monitored as well.
In case of infection,antibiotics can be prescribed.
It's good to make an appointment with your doctor.
Hope this helps.
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