What Causes Dizziness And Tingling Feeling In Head?

Hi, I have dizzy spells that are starti to get worse. THe feeling in my head is tingling like when ur foot falls asleep. And normally I see white dots but now I see pitch black and they are lasting longer. About 2 min long now. I was told before that it's because I don't eat enough salt and drink enough water but that can't be it. I eat a good amount of salt and I drink tons of water. What's foig on?