I have panic attacks. I would say, from my testing and observations, that the panic causes the high blood sugars, not the other way round, for me.
Low blood sugar levels however, which for me is under 4.5, can cause panicky feelings, shaking and irritability.
This is just my experience. And since lowering my carbs to help keep my blood sugar level more steady, the lower blood sugar problems have become less frequent.
Hugs for the panic attacks - they are horrid.