This has happened to my daughter over the past 5 years.

However she was diagnosed with migrainous vertigo which is a type of migraine that was triggered by the accident. She had never had migraines or headaches before the accident. The theory is that somewhere in her genetics she carried the migraine gene that got triggered or turned on by this accident.

Her symptoms are part PCS and part migraines. If you tickle the migraine enough your symptoms will get worse and worse. I believe her light sensitivity, nausea, vertigo, are part of the migraine. So yes your symptoms can get worse if you continue to tickle the migraine. We had plenty of doctors that prescribed therapy, like vestibular therapy, in which she went backwards and to this day she has not recovered to where she was.

She did a two day test up at UCSF that confirmed this.