My sister has attacks with severe headaches and sudden chills then it ends with shivering like fits?



 

My sister has attack of severe headache with sudden feeling of chills then it ends with shivering like fits and after painful stimulation she regain her breathe and coniousness.
In-between she is alert but drowsy with continous feeling of mild headache , nausea with vomiting sometime
The attacks at first was irregular bs later they became in fixed times between 2-3 pm and 2-3 am but we noticed when she make some physical activity she might have one attack again
All of her investigations are normal like
MRI/blood picture/CSF/liver & kidney functions/urine & stool and also her EEG was normal waves
They began with antiviral and anti bacterial with steroids and saline for 5 to 6 days with no response
Then recently thery started with her valporic acid 500 mg and the attacks stoped but at their times she have the same symptoms of severe headache and nausea
And in between she sleeps alot and still drowsy
Aslo there are some little symptoms like tinnitus and slight abdominal pain put not tender
My questions is those symptoms now from ther valporic acid ? Or the symptoms remain but the medication maken it little ?
Is there a psychic problem that can cause such attacks and she is only stressed or depressed ?
I hope you help me or advice to search for something the doctors are missing