Brief Answer:
as discussed below.

Detailed Answer:
Hi.
Thanks for your query and an elucidate history.

To recapitulate:
Female/48 - varied problems
Tender 1'' lump at base of skull -
migraines daily - botox not working now - migraine increased -
nausea, dizziness, bad memory, difficult recalling information -
low grade fever - sweating for no reason and fatigue -
-No other information provided about Doctor's visit, Medication and so on.

I would like to know a few more details for me to assist more:
-Since when is the lump at the base of skull present?
- Is there a hair loss on the lump?
- Have been seen by a Neurologist?
- What are the recent investigations done ?

I would advise in such a case the following: Please get all the relevant investigations done ASAP.
- MRI of the brain including that of the lump (can be done incidentally).
- Neurologist's opinion, if necessary a second opinion of another Neurologist, clinical evaluation and examination, detailed investigations.
- Tests of blood: CBC, liver, kidney functions.
- Blood Culture and sensitivity: blood sample to be taken when the fever is present .

The lump can be an infected sebaceous cyst and the best way is certainly to get this removed for a few reasons:
- You get rid of the lump which is not a normal part of the body.
- You get a confirmed diagnosis by Histopathological examination.

This way, all your problems will be diagnosed well and treated accordingly.

I hope this answer helps you, please feel free to ask further relevant medical queries if you need to or if you you feel that there is a gap-of-communication.

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Brief Answer:
Neurologist for review and General Surgeon for the lump.

Detailed Answer:
You certainly need a revaluation by a Neurologist and investigations too.

The lump can be seen by a General Surgeon and better be removed at an appropriate time.

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