Differential: epilepsy, pinched nerve (sciatic?) diabetic neuropathy,
Others: left bundle branch block.
Hello~You may have a pinched nerve in your neck, this can certainly cause the dizziness and passing out. I suggest seeing a chiropractor, he/she will take an x-ray of your neck and will be able to determine if this is the cause. If it is a few adjustments should have you feeling better. Also, you mentioned being diabetic, you may need your meds changed, you may even be having small seizures.
You need to be worked up for syncope or passing out spells. You need to go to the nearest Er and get admitted. You will be worked up for neurological and cardiac causes and will get an ekg, carotid ultrasound, echo, you ll be placed on a heart monitor while in the hospital and maybe even go home on one if nothing is to be found. But this is serious and you need to be checked out. Also please don't drive till further instructions from your physician