It can be "normal" for those with Chiari as you make the area smaller and tighter when you bend forward or backward...making the space for CSF to flow harder...and that is when symptoms can flare...
Each of us will have different issues with this condition, I could not turn my head to the left with out the same type of symptoms....
Try and avoid tilting your head backward...even at night when sleeping try not to bring your chin to your chest as that too can cause this sensation.
hi ....apart from chiari ...have you recently checked your BP?