Severe Headache and Faint. Taken ahead.

On 1st Aug,my friend faced unbearable headache and fainted .She got self-recovered after 30-40 mins .Consulted Neurologist & as asked did EEG,Blood test and plain Brain MRI. All the test are normal,only Thyroid Anti-body segment in blood report was above the range. However , have no thyroid problem .As per this unusual we believe doc prescribed few medicines. We continue medicines but headache is still there in every 3-4 days,even after increasing power of medicines by neurologist.Yet another incident happened yesterday,where she again had same painful headache ,weakness and lastly fainted for another 30-mins. We are under treatment from last 3 months , but see no improvement. Can you please help us know why it is occurring and what should be next steps to be taken ahead.