You must taper off the drug. This approach will help decrease the intensity of some of the unpleasant sensations (withdrawal) you describe. I recommend that you do this under the guidance of your doctor.

The brain zaps will eventually disappear. It is part of SSRI discontinuation syndrome. Nausea is also a common symptom. Anti-nausea medication can help. Mention this to your doctor.

I took paroxetine for awhile and found it caused many of the problems you described. Once, I stopped the drug, they all disappeared.