this is about my mom.she has been for the last 3 weeks,getting real weak and shakey in the legs then she falls to her knees.right before this happens she gets a real bad headache and dizzy after.I believe she might get real light headed during.she gets no exercise,loss of muscle mass,smokes,has unhealthy eating habbits,and has cancer in between lower spine.not on chemo right now.when she gets this and falls her body shakes from the shoulders downi cant get her to see her dr.what is this?