Spinal tap

I have convince myself that I have cancer cells in my spinal fluid. I have been treated for bc with mets to the brain only. The latest single met is 5mm but it rest on the part of the brain that is contected to your spine. The Dr. said it would be impossible for me to have any symptoms from this tiny met and there is no edema. I had headaches,nausea and my gait was a bit off. So I am convinced and scared out of my mind.