Talk to General Physician on Fever Flu Vomits

Since 3 days my sister in law is ill. It started with flu . Then fever. Now everything she eats she vomits it out. She cant even drink water. She went to a dentist few days back she had tooth infection so she had been taking antibiotics. Now she has pain and says i feel like i have no feeling in my left side of brain face leg and arm. We did all the tests all clear. Whats the matter? What should we do? We have been giving her pain killers for fever. Medicines for flu , medicine for vomits. But she is not improving