Hello & Welcome.
Try not to get to worried here. If you only did this once it could be a side affect. The brain chemistry on most drugs is affected and that could be why you have these brain zaps. Brain zaps happen to most of us who w/d off our meds or drugs. It will go away. Your heart should be fine. If the heart issue goes on then I would see a heart dr. Using once should not of damage it, it is more like a w/d symptom..However, I am not a Dr just speaking from my own experience.
Keep us updated!
I am sure others will chime in.
Hope all is better now.
Vickie