Completely possible to develop any kind of weird side effect such as you describe even after being on the medication for a long time.
In regards to CBD I use it for fibromyalgia pain, I have to stay vigilant with it every day for it to make a difference. Cant say for sure if it affects my energy levels at all, but my level of pain certainly affects my energy.
Brain zaps. Honestly, I have either a. Never experienced one or b. Never recognized or identified it as such. I do however experience what I call little episodes of dizziness, a head buzz not unlike how I feel when I am extremely overly tired, or vertigo from standing up too fast. Maybe that's a brain zap, but if it is, i have been lucky because they arent debilitating for me. I know many people experience horrible brain zaps and I'm sure you will get a lot of tips from them here.
My daily regimen includes omega 3 and vitamin D. Some CBD products maybe 500 or 1000 mg, protein, carbs that arent enriched with b vitamins or folic acid as I have MTHFR mutation (most people do!) and take methylated B/folate. Practice acceptance and commitment therapy. Water. Epsom salt baths for relaxation and magnesium. Sleep.
You can do this. Many have gone through it and lived to tell the tale. You won't die over it although sometimes you think you will. You've got a great trip coming up to look forward to and you will be feeling great by then. Glad you found us!