Chingona,
I have been reading about migraine in recent months and it is quite a common aura of migraine to have a sense of dread at its initiation. It also seems to me quite difficult to distinguish migraine and seizure as either can have similar symptoms. So I’m sure the panic you feel occasionally is provoked by whatever your AVM is doing and you might look upon it as “false”, a feeling that is induced in you rather than something “true” wherein you should really believe there is anything to fear. Put it aside as a natural consequence of the effect of your AVM.
The significant swings you describe sound a bit bipolar to me: bipolar affective disorder: I can’t remember if you already acknowledged bipolar in one of your posts or I am joining up information with something I’ve read about someone else. But again, massive swings in mood are a feature of bipolar. I do find it quite remarkable that you have such big swings and can have quite disabling days and other days when you might go cycling.
I hope this might help,
Richard