your symptos sound exactly like those of hydrocephalus. Particularly if your headache is a "forhead" headache, as I call them, with a sensation of being hit by a hammer from the inside. That along with the vomiting (another sign of increased intracranial pressure) are typical symptoms I have when my shunt blocks.
I would go back to the hospital and insist on a CT scan immediately, because you could be putting yourself in danger by delaying treatment. I can't believe your CT scans would have shown up "normal" while you are experiencing these symptoms.
Hang in there!
Nat.