How To Treat Numbness From Neck Towards Cervical Bulging Disc?

when i stand up and walk one or two steps, i feel all the symptoms of fainting. to stop the reaction, i stand still and hold on to a wall. my md said i lack water and sodium but i feel numbness from my neck downwards from cervical bulging dics and lumbar bulging discs. 70 oz of water and salting everything is not working. any advice? i am 49, 5' 3 and 1/2 inches and have recently gained 30 lbs in 5 months and weigh 260 lbs. i have fibromyalgia and pernicious anemia. the near-fainting occurs about 4 to 6 times per day.