Hello~Your condition definitely sounds like it could be helped by some chiropractic adjustments. It sounds like you have some pinched nerves along with misaligned vertebrae in your spine. You could also have some vertebral misalignment in you neck, this could possibly cause the flash of numbness and other feelings that you had.
I would however, ask your PCP for a carotid arterial scan, there could possibly be some minute blockages in your carotid arteries causing the dizziness and feelings like you will black out and are numb, this would be called a TIA (Little stroke) I am not saying it is, but when I hear symptoms like this, I always feel it is best to have it checked, it may prevent a full blown stroke later on. I don't want to scare you, I am just suggesting that issues like this should be looked into.
I hope you feel better soon. God bless you.