She smoked weed. Tripped out. Her paranoia and inability to recognize a high from something bad happening made her think she had symptoms. She went to the doctor, who told her she had an imbalance problem after she explained her "symptoms."
...? Was there any test performed that proves the imbalance problem (CT scan, or MRI)?
Sounds like she had a bad trip and wants to blame it on the drugs rather than being a newb idiot. I don't know for sure, but I believe girls say their "drink has been drugged" a lot when really they just drank a lot and blacked out.