I have a B12 deficiency and have had 2 MRI s. They say I have a 4mm tumor which is benign in my brain and has not grown. Nothing to worry about, however, I also have like vertigo, when I position my head. Also I feel like I m out of balance, my eyes are jumpy, everyone says I m fine. What could this be? I also have twitching at times on my left thumb and lip